Attentive readers might have noticed my absence over the last couple of weeks. I’ve been trying to recover from a bout of illness.
It got me thinking about the immune system, and how little I know about my own immune health. The vast array of cells, proteins, and biomolecules that works to defend us from disease is mind-bogglingly complicated. Immunologists are still getting to grips with how it all works.
Those of us who aren’t immunologists are even more in the dark. I had my flu jab last week and have no idea how my immune system responded. Will it protect me from the flu virus this winter? Is it “stressed” from whatever other bugs it has encountered in the last few months? And since my husband had his shot at the same time, I can’t help wondering how our responses will compare.
So I was intrigued to hear about a new test that is being developed to measure immune health. One that even gives you a score.
The test David took was developed by John Tsang at Yale University and his colleagues. The team wanted to work out a way of measuring how healthy a person’s immune system might be.
Tsang and his colleagues wanted to measure “deviation from health.” They looked at blood samples from 228 people who had immune diseases that were caused by single-gene mutations, as well as 42 other people who were free from disease. All those individuals could be considered along a health spectrum.
Another major challenge lies in trying to capture the complexity of the immune system, which involves hundreds of proteins and cells interacting in various ways. (Side note: Last year, MIT Technology Review recognized Ang Cui at Harvard University as one of our Innovators under 35 for her attempts to make sense of it all using machine learning. She created the Immune Dictionary to describe how hundreds of proteins affect immune cells—something she likens to a “periodic table” for the immune system.)
Tsang and his colleagues tackled this by running a series of tests on those blood samples. The vast scope of these tests is what sets them apart from the blood tests you might get during a visit to the doctor. The team looked at how genes were expressed by cells in the blood. They measured a range of immune cells and more than 1,300 proteins.
The team members used machine learning to find correlations between these measurements and health, allowing them to create an immune health score for each of the volunteers. They call it the immune health metric, or IHM.
When they used this approach to find the immune scores of people who had already volunteered in other studies, they found that the IHM seemed to align with other measures of health, such as how people respond to diseases, treatments, and vaccines. The study was published in the journal Nature Medicine last year.
The researchers behind it hope that a test like this could one day help identify people who are at risk of cancer and other diseases, or explain why some people respond differently to treatments or immunizations.
But the test isn’t ready for clinical use. If, like me, you’re finding yourself curious to know your own IHM, you’ll just have to wait.
This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.
MIT Technology Review Explains: Let our writers untangle the complex, messy world of technology to help you understand what’s coming next. You can read more from the series here.
“Like riding a bike” is shorthand for the remarkable way that our bodies remember how to move. Most of the time when we talk about muscle memory, we’re not talking about the muscles themselves but about the memory of a coordinated movement pattern that lives in the motor neurons, which control our muscles.
Yet in recent years, scientists have discovered that our muscles themselves have a memory for movement and exercise.
When we move a muscle, the movement may appear to begin and end, but all these little changes are actually continuing to happen inside our muscle cells. And the more we move, as with riding a bike or other kinds of exercise, the more those cells begin to make a memory of that exercise.
When we move a muscle, the movement may appear to begin and end, but all these little changes are actually continuing to happen inside our muscle cells.
We all know from experience that a muscle gets bigger and stronger with repeated work. As the pioneering muscle scientist Adam Sharples—a professor at the Norwegian School of Sport Sciences in Oslo and a former professional rugby player in the UK—explained to me, skeletal muscle cells are unique in the human body: They’re long and skinny, like fibers, and have multiple nuclei. The fibers grow larger not by dividing but by recruiting muscle satellite cells—stem cells specific to muscle that are dormant until activated in response to stress or injury—to contribute their own nuclei and support muscle growth and regeneration. Those nuclei often stick around for a while in the muscle fibers, even after periods of inactivity, and there is evidence that they may help accelerate the return to growth once you start training again.
Sharples’s research focuses on what’s called epigenetic muscle memory. “Epigenetic” refers to changes in gene expression that are caused by behavior and environment—the genes themselves don’t change, but the way they work does. In general, exercise switches on genes that help make muscles grow more easily. When you lift weights, for example, small molecules called methyl groups detach from the outside of certain genes, making them more likely to turn on and produce proteins that affect muscle growth (also known as hypertrophy). Those changes persist; if you start lifting weights again, you’ll add muscle mass more quickly than before.
In 2018, Sharples’s muscle lab was the first to show that human skeletal muscle has an epigenetic memory of muscle growth after exercise: Muscle cells are primed to respond more rapidly to exercise in the future, even after a monthslong (and maybe even yearslong) pause. In other words: Your muscles remember how to do it.
Subsequent studies from Sharples and others have replicated similar findings in mice and older humans, offering further supporting evidence of epigenetic muscle memory across species and into later life. Even aging muscles have the capacity to remember when you work out.
At the same time, Sharples points to intriguing new evidence that muscles also remember periods of atrophy—and that young and old muscles remember this differently. While young human muscle seems to have what he calls a “positive” memory of wasting—“in that it recovers well after a first period of atrophy and doesn’t experience greater loss in a repeated atrophy period,” he explains—aged muscle in rats seems to have a more pronounced “negative” memory of atrophy, in which it appears “more susceptible to greater loss and a more exaggerated molecular response when muscle wasting is repeated.” Basically, young muscle tends to bounce back from periods of muscle loss—“ignoring” it, in a sense—while older muscle is more sensitive to it and might be more susceptible to further loss in the future.
Illness can also lead to this kind of “negative” muscle memory; in a study of breast cancer survivors more than a decade after diagnosis and treatment, participants showed an epigenetic muscle profile of people much older than their chronological age. But get this: After five months of aerobic exercise training, participants were able to reset the epigenetic profile of their muscle back toward that of muscle seen in an age-matched control group of healthy women.
What this shows is that “positive” muscle memories can help counteract “negative” ones. The takeaway? Your muscles have their own kind of intelligence. The more you use them, the more they can harness it to become a lasting beneficial resource for your body in the future.
Bonnie Tsui is the author of On Muscle: The Stuff That Moves Us and Why It Matters(Algonquin Books, 2025).
This is today’s edition of The Download, our weekday newsletter that provides a daily dose of what’s going on in the world of technology.
How do our bodies remember?
“Like riding a bike” is shorthand for the remarkable way that our bodies remember how to move. Most of the time when we talk about muscle memory, we’re not talking about the muscles themselves but about the memory of a coordinated movement pattern that lives in the motor neurons, which control our muscles.
Yet in recent years, scientists have discovered that our muscles themselves have a memory for movement and exercise. And the more we move, as with riding a bike or other kinds of exercise, the more those cells begin to make a memory of that exercise. Read the full story.
—Bonnie Tsui
This piece is part of MIT Technology Review Explains: our series untangling the complex, messy world of technology to help you understand what’s coming next. You can read more from the series here.
This story is also from our forthcoming print issue, which is all about the body. If you haven’t already, subscribe now to receive future issues once they land. Plus, you’ll also receive a free digital report on nuclear power.
2025 climate tech companies to watch: Traton and its electric trucks
Every day, trucks carry many millions of tons of cargo down roads and highways around the world. Nearly all run on diesel and make up one of the largest commercial sources of carbon emissions.
Traton, a subsidiary of Volkswagen, is producing zero-emission trucks that could help clean up this sector, while also investing in a Europe-wide advanced charging network so other manufacturers can more easily follow suit. Read the full story.
—Amy Nordrum
Traton is one of our 10 climate tech companies to watch—our annual list of some of the most promising climate tech firms on the planet. Check out the rest of the list here.
This test could reveal the health of your immune system
We know surprisingly little about our immune health. The vast array of cells, proteins, and biomolecules that works to defend us from disease is mind-bogglingly complicated. Immunologists are still getting to grips with how it all works.
Now, a new test is being developed to measure immune health, one that even gives you a score. But that’s a difficult thing to do, for several reasons. Read the full story.
—Jessica Hamzelou
This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, sign up here.
The must-reads
I’ve combed the internet to find you today’s most fun/important/scary/fascinating stories about technology.
1 China is cracking down on imports of Nvidia’s AI chips Customs officers are combing shipments looking for the company’s China-specific chips. (FT $) + US officials are investigating a firm that’s suspected of helping China sidestep export restrictions. (NYT $)
2 Tesla’s ‘full self-driving’ feature is under investigation After multiple reports of vehicles using it ran red lights. (WP $) + The company is slashing its prices to compete with Chinese giant BYD. (Rest of World) + Elon Musk will still receive billions, even if he fails to achieve his ambitions goals. (Reuters)
3 A data hoarder has created a searchable database of Epstein files Making it simple to find mentions of specific people and locations. (404 Media)
4 OpenAI says GPT-5 is its least-biased model yet Even when proceeding with “challenging, emotionally charged prompts.” (Axios)
5 The developers behind ICE-tracking apps aren’t giving up They’re fighting Apple’s decision to remove their creations from its app store. (Wired $) + Another effort to track ICE raids was just taken offline. (MIT Technology Review)
6 The world’s biodiversity crisis is worsening More than half of all bird species are in decline. (The Guardian) + The short, strange history of gene de-extinction. (MIT Technology Review)
7 YouTube is extending an olive branch to banned creators It’s overturned a lifetime ban policy to give the people behind previously-banned channels a second chance. (CNBC) + But users kicked off for copyright infringement or extremism aren’t eligible. (Bloomberg $)
8 This startup wants to bring self-flying planes to our skies Starting with military cargo flights. (WSJ $)
9 Your plumber might be using ChatGPT They’re increasingly using the chatbot to troubleshoot on the ground. (CNN)
10 Do robots really need hands? Maybe not, but that’s not standing in the way of researchers trying to recreate them. (Fast Company $) + Will we ever trust robots? (MIT Technology Review)
Quote of the day
“Social media is a complete dumpster.”
—Hany Farid, a professor of computer science at the University of California, Berkeley, describes the proliferation of AI slop videos infiltrating digital platforms to the New York Times.
One more thing
Who gets to decide who receives experimental medical treatments?
There has been a trend toward lowering the bar for new medicines, and it is becoming easier for people to access treatments that might not help them—and could even harm them. Anecdotes appear to be overpowering evidence in decisions on drug approval. As a result, we’re ending up with some drugs that don’t work.
We urgently need to question how these decisions are made. Who should have access to experimental therapies? And who should get to decide? Such questions are especially pressing considering how quickly biotechnology is advancing. We’re not just improving on existing classes of treatments—we’re creating entirely new ones. Read the full story.
—Jessica Hamzelou
We can still have nice things
A place for comfort, fun and distraction to brighten up your day. (Got any ideas? Drop me a line or skeet ’em at me.)
+ I love this crowd-sourced compendium of every known Wilhelm scream in all sorts of media. + Happy birthday to pocket rocket Bruno Mars, who turned 40 this week. + Here’s how to visit an interstellar interloper. + Bumi the penguin is having the absolute time of their life with this bubble machine
For 12 years Andrei Rebrov managed infrastructure and operations at Scentbird, a perfume subscription company he co-founded in 2013. He learned the importance of acquiring the right subscribers, those who stay and generate lifetime value for the business.
The key, he says, was accurate, timely analytics to assess channels, creative, and promos. Finsi, his new company, provides those metrics, enabling merchants to predict a prospect’s value over the long term.
In our recent conversation, I asked Andrei to share acquisition tactics, churn avoidance, product selection, and more.
Our entire audio dialog is embedded below. The transcript is edited for length and clarity.
Eric Bandholz: Tell our listeners who you are and what you do.
Andrei Rebrov: I’m the co-founder of Finsi, an analytics platform for subscription-based businesses, launched in 2024. We help companies acquire and retain profitable subscribers.
Before that, I spent 12 years building and scaling Scentbird, a perfume subscription service, where I served as CTO.
I handled much of the engineering, including coding the website, building back-office systems, and managing online payments and warehouse infrastructure. We launched in August 2014 and surpassed 1 million subscribers by the end of 2024. I left the company in March 2025.
We started Scentbird alongside subscription pioneers such as cosmetic brands Ipsy and Birchbox, and apparel provider Fabletics. We were inspired by Warby Parker’s “try before you buy” model, and we applied the concept to fragrances. We built our own platform, which gave us flexibility and scalability over the years.
We began with fragrances from other brands. Some were hesitant, but over time, Scentbird became a mutually beneficial partner, giving brands access to younger audiences, online shoppers, and consumers who wanted to try before committing to a full bottle. Our website’s motto became: “Date your fragrance before you marry it.”
Customers could select their monthly fragrances or receive a default “fragrance of the month.” Thousands chose the default, enabling the rapid collection of reviews and insights that brands could use to refine formulas, marketing copy, and strategies.
Subscription businesses require nonstop acquisition to stay in place. The challenge isn’t just reducing churn; it’s acquiring customers who will stay. Most SaaS companies separate acquisition and retention teams, which can create disconnects. Success comes from collaboration — aligning acquisition, retention, and operations — so the entire company functions as one system. Increasing customer acquisition spend is usually worthwhile if it improves lifetime value.
We were vertically integrated, which meant that fulfillment, logistics, and marketing had to move together. If one team outpaced the others, something would break quickly.
Bandholz: What drives profitable acquisition?
Rebrov: Accurate analytics. It’s one of the hardest parts of running a subscription business, and it’s a big reason I started Finsi. At Scentbird, we invested early in analytics because every acquisition channel behaves differently. Each has its own lifetime value, payback period, and acquisition cost, so analyzing them separately was essential.
We needed to understand what customers purchased through each channel and how these purchases affected retention. Traditional LTV calculations rely on historical data, which is typically dated. That delay makes it impossible to know if current strategies are working. To solve this, we built predictive LTV models that provided early insight — often within a month — so we could gauge the impact of new creatives and A/B tests faster.
For example, we tested a two-product-per-month plan. It initially lowered conversion rates, but predictive data revealed much stronger long-term value. That insight helped justify warehouse adjustments for the new fulfillment process.
We explored various customer acquisition channels. TikTok Shops became a top performer. Since it integrated only through Shopify, we built a faceless Shopify store connected to TikTok, routed orders through it, and shipped sample bundles to introduce users to the Scentbird experience before converting them into subscribers.
We grandfathered long-term subscribers to reward loyalty. Some stayed seven or eight years, though many churned within 12 months. Early, accurate analytics made it possible to balance growth and retention effectively.
Bandholz: What size company benefits from Finsi’s analytics?
Rebrov: It’s less about size and more about the growth stage. Each stage faces different challenges. One of the biggest is cash flow. Every physical SKU has its own lead time, so if inventory takes three months, companies must accurately forecast demand, churn, and cash flow. For early-stage brands, those with annual revenue under $10 million, we help stabilize operations and predict cash needs.
At $10 to $50 million, segmentation becomes crucial: identifying lapsed customers for personalized win-backs and recognizing high-value customers early to offer premium experiences.
At $50 to $150 million, the focus shifts to eliminating surprises and aligning systems, ensuring promotions run correctly and teams understand how one decision impacts another. Larger brands often expand into new product lines and face the same scaling issues again. Across all stages, success depends on accurate, unified data to guide smarter decisions.
Effective retention depends on understanding why customers cancel.
Bandholz: How do you do that?
Rebrov: We usually start with surveys to gather both structured and unstructured feedback. Multiple-choice questions provide quantifiable insights, but the real value lies in open-ended responses, where customers share their personal stories. Surveys let you reach thousands of people efficiently, but phone conversations are invaluable. Talking directly with customers often reveals unique motivations and use cases that spark creativity and guide product development.
Spending even 30 minutes on the phone with a few customers, especially loyal ones, can uncover more insights than analytics ever could.
Certain products naturally fit subscriptions. Examples are consumable supplements, protein powders, and snacks. But infrequently purchased goods are better suited for one-off sales.
Companies must decide early because it shapes their marketing strategy. For traditional ecommerce, profitability often depends on the first sale. You aim to cover acquisition, cost of goods, and shipping upfront, often by selling bundles.
For subscriptions, the focus shifts to lifetime value. Sellers can afford to lose money initially if they know the customer will stay long enough to become profitable. Predictive LTV helps qualify customers early and informs how much you can spend to acquire them.
Simplicity wins. Don’t confuse prospects with multiple purchase paths or offers. Ensure a “subscribe and save” offer is consistent and easy to understand.
The beauty of subscriptions lies in predictable cash flow. Yet rising acquisition costs make retention even more vital.
Bandholz: Where can people follow you, reach out to you, or hire your services?
Google has quietly updated its list of user-triggered fetchers with new documentation for Google NotebookLM. The importance of this seemingly minor change is that it’s clear that Google NotebookLM will not obey robots.txt.
Google NotebookLM
NotebookLM is an AI research and writing tool that enables users to add a web page URL, which will process the content and then enable them to ask a range of questions and generate summaries based on the content.
Google’s tool can automatically create an interactive mind map that organizes topics from a website and extracts takeaways from it.
User-Triggered Fetchers Ignore Robots.txt
Google User-Triggered Fetchers are web agents that are triggered by users and by default ignore the robots.txt protocol.
According to Google’s User-Triggered Fetchers documentation:
“Because the fetch was requested by a user, these fetchers generally ignore robots.txt rules.”
Google-NotebookLM Ignores Robots.txt
The purpose of robots.txt is to give publishers control over bots that index web pages. But agents like the Google-NotebookLM fetcher aren’t indexing web content, they’re acting on behalf of users who are interacting with the website content through Google’s NotebookLM.
How To Block NotebookLM
Google uses the Google-NotebookLM user agent when extracting website content. So, it’s possible for publishers wishing to block users from accessing their content could create rules that automatically block that user agent. For example, a simple solution for WordPress publishers is to use Wordfence to create a custom rule to block all website visitors that are using the Google-NotebookLM user agent.
Another way to do it is with .htaccess using the following rule:
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Google-NotebookLM [NC]
RewriteRule .* - [F,L]
Google has released Lighthouse 13 with a broad audit consolidation that aligns Lighthouse reports with Chrome DevTools’ newer insight model.
The update is available now via npm and Chrome Canary. It will roll into PageSpeed Insights within about a week and is slated for Chrome’s stable channel with version 143.
Google says the update doesn’t change how Lighthouse calculates performance scores. This update targets non-scored audits only.
Lighthouse 13 Details
Audit Consolidation
Lighthouse 13 replaces many legacy audits with “insights” that mirror DevTools.
Notable examples include:
CLS And Layout:layout-shifts becomes cls-culprits-insight for clearer identification of layout shift causes.
Server And Network:document-latency-insight consolidates redirects, server response time, and text compression checks.
Images:image-delivery-insight replaces modern formats, optimized images, responsive images, and efficient animated content audits.
LCP: Two insights break down Largest Contentful Paint issues: lcp-discovery-insight and lcp-phases-insight. For interaction work, see interaction-to-next-paint-insight (INP).
Third-Party:third-parties-insight replaces the older third-party summary to show external script impact.
Additional replacements address DOM size, duplicated JavaScript, font display, legacy JavaScript, HTTP/2 and modern HTTPS, network dependency trees, render-blocking, caching, and viewport configuration.
Audits Removed Without Replacements
Several audits were removed because they are outdated, inactionable, or low value in modern environments. Additionally, some audits were removed because they were costly to run.
Removed audits include:
first-meaningful-paint
font-size
offscreen-images
preload-fonts
uses-rel-preload
no-document-write
uses-passive-event-listeners
third-party-facades
Minor Differences From Earlier Previews
Google kept non-composited-animations and unsized-images as separate diagnostics to help locate issues that don’t directly cause CLS.
Google also removed font-size and preload-fonts even though those were not in the initial removal list.
Why This Matters
If you rely on Lighthouse for client reporting, you will see fewer line items and more consolidated insights that map to DevTools.
Your scores shouldn’t change just by upgrading, but any automation that keys off audit IDs will need to track the new insight identifiers.
For SEO context, the removal of the font-size audit reflects Google’s position that this is not a current SEO signal, even though legibility remains a UX consideration.
Looking Ahead
Expect Lighthouse and DevTools to stay aligned on the same insight model.
For reporting, consider mapping old audit IDs to the new insights now to avoid broken dashboards when PSI updates.
Two critical vulnerabilities were identified in the WP Travel Engine, travel booking plugin for WordPress that’s installed on more than 20,000 websites. Both vulnerabilities enable unauthenticated attackers to obtain virtually complete control of a website and are rated 9.8 on the CVSS scale, very close to the highest possible score for critical flaws.
WP Travel Engine
The WP Travel Engine is a popular WordPress plugin used by travel agencies to enable users to plan itineraries, select from different packages, and book any kind of vacation.
Improper Path Restriction (Path Traversal)
The first vulnerability comes from improper file path restriction in the plugin’s set_user_profile_image function
Because the plugin fails to validate file paths, unauthenticated attackers can rename or delete files anywhere on the server. Deleting a file such as wp-config.php disables the site’s configuration and can allow remote code execution. This flaw can enable an attacker to stage a remote code execution attack from the site.
Local File Inclusion via Mode Parameter
The second vulnerability comes from improper control of the mode parameter, which lets unauthenticated users include and run arbitrary .php files
This enables an attacker to run malicious code and and access sensitive data. Like the first flaw, it has a CVSS score of 9.8 and is rated as critical because it allows unauthenticated code execution that can expose or damage site data.
Recommendation
Both vulnerabilities affect versions up to and including 6.6.7. Site owners using WP Travel Engine should update the plugin to the latest version as soon as possible. Both vulnerabilities can be exploited without authentication, so prompt updating is recommended to prevent unauthorized access.
YouTube is piloting a policy change that allows some previously terminated creators to request a new channel after a one-year waiting period.
The program will roll out to eligible creators over the coming weeks and months, according to YouTube’s official announcement.
How The Second Chances Pilot Works
Eligible creators will start seeing an option in YouTube Studio (desktop) to request a new channel when signed in with their previously terminated channel credentials.
The YouTube Team wrote:
“We know many terminated creators deserve a second chance… we’ve had our share of second chances to get things right with our community too.”
Creators become eligible to apply one year after termination. During that year, they can still appeal the original decision if they believe YouTube made a mistake.
What A New Channel Includes
YouTube frames this as a fresh start rather than a restoration of the original channel. Creators can rebuild their community and may re-upload prior videos that comply with current Community Guidelines.
Once the new channel meets the YouTube Partner Program criteria, creators can apply for monetization like any other channel.
Eligibility & Exclusions
When reviewing requests, YouTube says it will consider factors such as whether violations were severe or persistent and whether on- or off-platform activity harmed, or could continue to harm, the YouTube community.
YouTube cites channels that endangered kids’ safety as an example that may be disqualified.
The pilot does not apply to:
Creators terminated for copyright infringement
Creators who violated Creator Responsibility policies
Creators who deleted their YouTube channel or Google account
Appeals Versus New Channel Requests
Appeals remain available for one year after termination. YouTube says appeals are evaluated based on how policies apply at the time of the appeal.
Successful appeals reinstate the original channel with its content and subscribers. If the appeal is unsuccessful, the creator may request a new channel after one year.
Why This Matters For Marketers
The pilot softens the finality of termination without fully removing the consequences.
Creators may re-upload compliant videos, but they’ll still need to rebuild from scratch on new channels.
Looking Ahead
YouTube says it will monitor the pilot and adjust as it learns from early applications.
For more details, see the video from YouTube’s Creator Liaison below:
Yoast SEO is a free WordPress SEO plugin that helps your site perform better in search engines like Google. It also gives you the tools to bring your content to the highest SEO and overall readability standards. Here, we’ll explain how our plugin helps you build the best website possible!
Table of contents
What Yoast SEO does
Yoast SEO offers many tools and features to boost your SEO. Some of these features influence the SEO of your whole site, while others help you optimize individual posts and pages for search engines.
At Yoast, we believe in our mission, “SEO for everyone,” so you can access all the essential WordPress SEO tools in our free Yoast SEO plugin. But if you really want to boost your SEO, upgrade to Yoast SEO Premium. This upgrade gives you even more amazing SEO features, including great AI features like Yoast AI Optimize and AI Summarize! Keep reading to find out what Yoast SEO can do for your SEO!
SEO for your posts and pages
If you want your posts and pages to appear in the search results, you need to optimize them! So, when you use WordPress to create/edit posts, you’ll find a lot of Yoast SEO tools to help you draft and optimize great content. And if you think SEO optimization is all about keywords, think again. The tools and tips in our Yoast SEO plugins also focus on quality content and user experience. Trust us, because it will all help your rankings, directly or indirectly.
Here’s how the plugins will help you optimize your posts and pages:
Make sure you’re optimizing correctly (we’ll tell you if you aren’t)
After you’ve done your keyword research, you’ll have to start optimizing the pages and posts on your sites for the keywords and keyphrases you want to rank for. To do that, you can set a focus keyphrase for an article in Yoast SEO. Then, the plugin uses our content SEO analyses to determine how your content scores on different factors. It checks how many times you use your keyphrase, the length of your text, or whether you used any internal links.
The results of these analyses guide you in optimizing your post or page to rank with your chosen keyphrase. You’ll see red, orange, and green traffic lights to indicate how every factor scores. This gives you an overview of the overall score and what you can still tackle to increase your rankings!
We also give you tools to find out which keywords you can target successfully, and track how successful your content really is. For the keyword research part, we integrate with the leading online marketing platform, Semrush. For tracking the performance of your content in search, we integrate with the rank tracking platform Wincher.
The content SEO analysis tells you how to optimize your text for a certain keyword with the use of red, orange, and green traffic lights.
Guidance for writing high-quality content — in many languages!
Optimizing your content to rank with the right keyphrase is important, but don’t forget your reader! Even if you write amazing content for search engines, your audience won’t benefit from it if they don’t understand it. When a person doesn’t understand your content, the chance of them buying something from you is close to zero. The same is true for the odds of them sharing one of your articles with their friends. So, you must ensure your content is also easy to understand. And that’s where the readability features come in.
Our readability checks let you adopt the feedback in a way that suits you, without losing your personal touch. If you’re interested in all the factors that increase readability, you can read more about the Yoast SEO readability features. What’s more, you can optionally enable the inclusive language analysis alongside readability and SEO checks
The readability analysis tells you how to optimize your text to make it read easily using red, orange, and green traffic lights
All or most features are available in the following languages: English, German, Dutch, French, Spanish, Italian, Portuguese, Czech, Russian, Polish, Swedish, Hungarian, Indonesian, Arabic, Hebrew, Turkish, Norwegian, Japanese, Slovak, and Greek.* We support more languages at various levels. Check the overview for other languages.
* Unfortunately, it’s not possible to calculate the Flesch reading ease score for some of these languages. Check the overview below to see which languages.
Based on years of research
Yoast SEO’s readability features are well-researched analyses that give you feedback on how to optimize your writing. Now, this may sound strange, because the way you write can be very personal. Let us explain how it works.
The plugin uses an algorithm to check your content for factors that are proven to increase readability. We look at the use of transition words, the use of passive voice, sentence and paragraph lengths, word complexity, and more. However, we carefully crafted this algorithm to be as accurate as possible without being too strict.
Influence what Google shows in search results
Of course, you don’t just want your pages to appear in Google’s search results. You want your search results to look amazing, too! That’s why Yoast SEO has tools to let you plan and preview how each page will (probably) look when it appears on Google. This is probably something we can’t avoid here, as Google will occasionally decide it knows better and show something else instead. But by optimizing certain outputs on your page, you can indicate how Google should present your content to users. And that’s still something worth doing.
Titles and meta descriptions
With our plugin, you can specify an SEO title (the ‘headline’ of your search result) and a meta description (a short piece of text underneath your search headline, describing what users can find on your page) for each new page you publish. We’ll let you know if these are too long or if your keyword is missing. If you want to, you can also set defaults for all your pages.
The search appearance section of Yoast SEO shows how your content will look in the SERPs
You might have seen search results that contain extra parts beyond the usual headline-and-description format before. The example below contains recipes with extra information like reviews, cooking time, ingredients, and images, for instance. And that’s just one example. Extra information can be added for all kinds of results, including products!
A structured data-powered search result in Google for recipes
The way to get results like this is by using Schema structured data. We won’t lie: it’s complex, technical stuff. Luckily for you, you won’t need to know a thing about the tech wizardry behind it. Just having Yoast SEO installed means you’ll automatically have structured data output for your pages. All you need to do is select a few options to make sure it suits your needs.
Manage social outputs
Now, social media isn’t strictly a part of SEO. But when you make great content, you often want to share that content on your social feeds, too. That’s why Yoast SEO also comes with Facebook and X previews that you can adjust to make sure your content is always looking great, whoever is sharing it. You can set a specific title, description and OpenGraph image for each post. Again, if you prefer to set one standard structure for all posts, there’s an option to do that.
Technical SEO for your website
We’ve taken a look at what Yoast SEO can do for your posts and pages. But what can it do for your site overall? If technical SEO isn’t your strong suit, much of the following may not make sense to you. But don’t worry! Yoast SEOexists to make sure you don’t have to know all of these things.
Set up your site for SEO
The plugin settings are very sensible by default, and our first-time configuration also guides you through the steps to get your technical SEO settings right. Behind the scenes, our hidden features will also gear you up with an XML sitemap, a robots.txt file, site-level Schema structured data, and more.
The free version of Yoast SEO automatically generates XML sitemaps for your website, making it easier for search engines like Google to find and index your content. These sitemaps update on their own whenever you add or remove pages, so you don’t have to do any manual work. In addition, Yoast SEO gives you easy access to your site’s robots.txt file. From the plugin, you can view or edit this file to control which parts of your site search engines are allowed to crawl. Both features help search engines discover your content while giving you more control over your site’s visibility.
Thanks to Yoast SEO, you can now quickly and without additional cost add an llms.txt file to your site to guide AI systems toward your most valuable content. This simple text file helps AI tools identify and prioritize key pages efficiently, ensuring they focus on what matters most to your site.
Manage your content
As you write more and more content for your site, you’ll be looking for easy ways to manage it! The Yoast SEO plugin comes with a few features to help you manage your content well and avoid common SEO issues. For instance, when you make changes like deleting a page or changing a URL, if you don’t know what you’re doing, then things can get messy. And if you make a lot of similar pages, that can be a problem too, as Google doesn’t know which one it should direct users towards. To help you deal with SEO issues like these, Yoast SEO comes with two unmissable tools: canonical URL tags and the Redirects tool.
Canonical URLs
Canonical URLs are really helpful if you have a lot of similar content, such as a webshop with multiple variants of the same product, each having its own page. To make life easy for you, Yoast SEO automatically adds canonical tags to all content marked for indexing. All of the canonical tags will be taken care of in the background; in most cases, you won’t need to change a thing. If you do need to adjust your canonical URL tags, it’s easy to do so.
Managing redirects
Redirects are essential if you’re moving or removing content. The fact is, users will probably still find their way to the old URL, but the content they’re expecting won’t be there. That’s not only disappointing and frustrating for users, but it can also make it harder for Google to find and index your content, too. While advanced redirect management is part of Yoast SEO Premium, you can still handle basic changes using WordPress settings or other free plugins.
Managing redirects is easy with Yoast SEO Premium
Build your site structure and internal links
If you want findable content that really ranks, you need to take care of your site structure and internal linking. The Yoast SEO plugin comes with a few tools to help you manage how your content links together: there’s a text link counter, which will tell you how many incoming and outgoing internal links there are on a page, as well as an internal linking suggestions tool in Yoast SEO Premium (in the editor view), which can help you add more if necessary. These features help you build a strong site structure and make sure your important content is easy for visitors and search engines to find.
Even more technical features of Yoast SEO
By simply installing the plugin and following the steps in our configuration workout, you’re already fixing a lot of important technical SEO things for your site! We do these steps for you, so you don’t have to know about every little technical detail.
If you really want to know everything Yoast SEO can do for you, then take a look at the complete list of features. Additionally, if you are (a bit more) familiar with technical SEO, you might enjoy reading more about Yoast SEO’s hidden features that secretly level up your SEO!
Still need to learn about SEO? One of the biggest benefits of using the Yoast plugins is that they make it really easy to get started and learn as you go along! We’ll give you pointers to help you get everything right, as well as links to read more about how SEO works and how to do it.
If you want to keep learning about SEO, we also offer free training courses and resources in our Yoast SEO Academy and on our SEO blog. You can start with these basics to understand how SEO works and get more out of your website as you go.
A quick recap
In this article, we’ve shown you what Yoast SEO can do for your site. Our plugin helps you improve your content SEO by helping you set a keyphrase and telling you exactly how you can optimize your content to rank with this keyphrase. The plugin also helps you improve the readability of your content by providing feedback that you can easily incorporate into your own writing style. And last but not least, the Yoast plugin improves your technical SEO by taking care of a lot of technical things in the background.
Everything above is available in Yoast SEO’s free plugin, making it a great starting point for most WordPress users. If you ever want more advanced tools, you can always explore Yoast SEO Premium and its extra features.
Edwin is an experienced strategic content specialist. Before joining Yoast, he worked for a top-tier web design magazine, where he developed a keen understanding of how to create great content.
