Chrome extensions for SEO and marketing are small programs you install in the browser that add data or features to the page you're looking at: search volumes under Google's results, a site's meta tags, the tracking tags firing on a landing page, the technology a competitor uses. They don't replace a suite like Semrush or Ahrefs. They answer in ten seconds questions that would otherwise need an export.
On 29 September 2026 we opened the official Chrome Web Store listing of 26 extensions recommended in the articles that rank on this topic, and noted how many users they have, their rating, who publishes them and when they were last updated. On Google UK, four of the nine organic results on page one for "seo chrome extensions" date from 2024 or earlier, one from 2019. The seven guides we read for the Italian version of this article gave no update date for the extensions they recommend, and none mentioned the permissions those extensions ask for. You'll find both here.
The 26 extensions checked on the Chrome Web Store
The table collects the data read on the official listings. The user count is the rounded figure the store shows, and it's worldwide: Google doesn't publish it by country. The rating is out of 5, with the number of reviews in brackets.
| Extension | Users (worldwide) | Rating | Last updated | Published by |
|---|---|---|---|---|
| On-page SEO | ||||
| META SEO inspector | 200,000 | 4.4 (628) | 29 Sep 2026 | Andrea Doimo |
| Detailed SEO Extension | 600,000 | 4.9 (234) | 2 Jun 2026 | Ahrefs |
| SEO META in 1 CLICK | 1,000,000 | 4.9 (1,300) | 31 Aug 2024 | seo-extension.com |
| Redirect Path | 300,000 | 4.3 (200) | 14 May 2026 | Ayima |
| Lighthouse | 1,000,000 | 4.4 (334) | 25 Jun 2026 | |
| Keywords and competitors | ||||
| SEOquake | 1,000,000 | 4.5 (2,600) | 28 Sep 2026 | Semrush |
| Keywords Everywhere | 1,000,000 | 4.5 (5,700) | 17 Sep 2026 | Axeman Technology Solutions |
| Keyword Surfer | 600,000 | 4.2 (1,000) | 29 Jan 2026 | Surfer |
| Ahrefs SEO Toolbar | 400,000 | 4.4 (554) | 15 Sep 2026 | Ahrefs |
| MozBar | 900,000 | 3.3 (2,500) | 20 Sep 2026 | Moz |
| SEO Minion | 200,000 | 4.0 (796) | 22 Feb 2026 | Akash Mansukhani |
| Open SEO Stats | 200,000 | 4.6 (5,800) | 4 Jun 2024 | Open Admin Tools |
| Similarweb | 1,000,000 | 4.6 (3,800) | 29 Sep 2026 | Similarweb |
| Wappalyzer | 3,000,000 | 4.6 (2,000) | 29 Sep 2026 | Wappalyzer |
| Tracking and campaigns | ||||
| Tag Assistant | 3,000,000 | 3.9 (1,300) | 24 Sep 2026 | |
| Tag Assistant Companion | 500,000 | 3.1 (206) | 24 Sep 2026 | |
| Google Analytics Debugger | 600,000 | 4.2 (535) | 30 Dec 2024 | |
| Meta Ads Data Advisor | 3,000,000 | 3.9 (1,300) | 28 Sep 2026 | Meta |
| Content and everyday work | ||||
| Grammarly | 40,000,000 | 4.5 (43,100) | 28 Sep 2026 | Grammarly |
| GoFullPage | 11,000,000 | 4.9 (84,200) | 25 Sep 2026 | Full Page LLC |
| Loom | 8,000,000 | 4.6 (10,200) | 29 Sep 2026 | Atlassian |
| ColorZilla | 4,000,000 | 4.6 (3,900) | 22 May 2024 | Iosart Labs |
| WhatFont | 3,000,000 | 4.0 (2,100) | 4 Mar 2024 | chengyinliu.com |
| Hunter | 600,000 | 4.7 (12,500) | 12 Sep 2026 | Hunter Web Services |
| Claude | 16,000,000 | 2.8 (1,700) | 19 Sep 2026 | Anthropic |
| ChatGPT | 6,000,000 | 2.8 (819) | 4 Sep 2026 | OpenAI |
Three quick takeaways. Five of the 26 extensions haven't had an update since 2024, and they include tools still recommended in many guides, such as ColorZilla, WhatFont and Open SEO Stats. Two names have changed: Meta Pixel Helper is now called Meta Ads Data Advisor, and Similarweb has added "AI Traffic" to the title of its listing. And the official extensions of the two most widely used AI assistants have millions of users but a rating of 2.8, the lowest in the table.
How we chose the extensions
We started from the guides that rank on page one of Google for this topic, in English and in Italian, including the one from SEO.com. We kept the extensions cited by at least two sources, plus the ones we use in our day-to-day client work. SEOquake, Keyword Surfer, Ahrefs SEO Toolbar, Wappalyzer and Grammarly appear in four of the seven Italian guides we read. On Google UK the same names come back: the snippets of the Databox, GR0 and royalplugins.com lists on page one cite SEOquake, MozBar, Detailed SEO Extension, META SEO inspector, SEO Minion and Redirect Path.
For each one we looked at four things: whether it still exists, when it was last updated, who publishes it and whether the features that made it famous are free or tied to a subscription. The user count doesn't measure quality. It tells you whether there's a publisher behind it with a reason to maintain it.
On-page SEO: reading a page without opening the code
This is where extensions earn their place, because the information is already in the page's code and the extension puts it in order. Which checks are best done with an extension and which with other on-page SEO tools we explain separately.
META SEO inspector shows the title, description, headings, Open Graph tags and structured data, and flags the ones that are missing or too long. It's published by an Italian developer, Andrea Doimo, and its last update was on the very day we checked. To work out what to fix once you've opened it, see our guides to the meta title and the meta description.
Detailed SEO Extension does a similar job, with 600,000 users and a rating of 4.9. On its Chrome Web Store listing it's now published by Ahrefs. SEO META in 1 CLICK has a million users and the same rating, but hasn't been updated since August 2024. It's still available, but if you have to pick one of the three, go for one that's maintained.
Redirect Path, from Ayima, shows every hop between the URL you typed and the final one, with the status code of each. It's the quickest way to spot a chain of 301 redirects or a 302 left behind after a migration. Lighthouse, from Google, generates the report on performance, accessibility and SEO right in the browser. The same checks are built into Chrome's developer tools, so the extension mostly helps people who rarely open them. The numbers to look at are explained in our guide to Core Web Vitals.
Keywords and competitors: where the free part ends
Here the store listings say things the guides leave out. Almost all these extensions are the free way into a paid product, and the metrics that make them useful often sit behind an account.
- Ahrefs SEO Toolbar: the listing states that you need a subscription to see Ahrefs metrics, while the extension's basic tools stay free. We worked out what the rest costs in our guide to Ahrefs pricing.
- Keywords Everywhere: volumes, CPC and the 12-month trend are in the paid version. SEO Minion, another widely cited extension, is only available to people on Keywords Everywhere's Silver plan or above.
- Keyword Surfer: the exception. It shows search volumes directly in Google's results without asking for a subscription.
- MozBar: 900,000 users but the lowest rating among the SEO extensions, 3.3. The advanced features require Moz Pro, and the listing mentions a 48-hour cache introduced to use fewer of the plan's queries.
- SEOquake: works without an account. Connecting a free Semrush profile adds Authority Score and traffic data.
Two caveats about the numbers these toolbars show. First, they're estimates, built on different models by each provider: the same page can get very different volumes and authority scores from one tool to the next, as we explained when we wrote about domain authority. Second, they're least reliable on small keywords. In many UK B2B sectors the searches that matter get 10 or 20 a month, and at that level an estimate can be far off. For real volumes use the keyword research tool that best fits your case; for real clicks, Google Search Console.
For competitors, Wappalyzer (3 million users) tells you which CMS, ecommerce platform and analytics tools a site is built with. Similarweb estimates traffic and where it comes from. These are estimates too, and we measured how far off they can be in our guide on how to check a website's traffic.
Tracking and campaigns: the Google and Meta extensions
People who run campaigns use these extensions to check that tags actually fire, and this is where the lists are furthest behind.
Google has merged its tools. The Tag Assistant help page explains that Tag Assistant Legacy and Tag Assistant Companion have been combined into a single extension that supports the features of both. Companion, with 500,000 users, will be uninstalled automatically in the coming months. The extension to keep is Tag Assistant, which works with the web tool tagassistant.google.com to check gtag.js and Google Tag Manager. Google Analytics Debugger, the extension that writes the data sent to Google Analytics to the console, hasn't been updated since December 2024.
On the Meta side, Meta Pixel Helper still exists but under another name: Meta Ads Data Advisor, 3 million users, updated on 28 September 2026. According to the listing it's no longer just for checking that the pixel fires, but for connecting website and marketing data to Meta. Anyone looking for it under its old name in guides from 2022 won't find it.
If checking tags is the part of the job that eats most of your time before each launch, it's one of the checks we carry out at the start of every project in our Google Ads service.
Content, design and everyday work
These are the extensions with the most users overall. Grammarly has 40 million, GoFullPage 11 million for capturing a whole page in a single screenshot, Loom 8 million for recording screen videos. They're in good health: all updated in September 2026.
For design, ColorZilla (4 million) and WhatFont (3 million) are the most cited for picking up a colour or a font from a site. Both have been static since 2024, since May and March respectively. They can still be installed, but they're two candidates to replace when they stop working.
Hunter finds the public email addresses linked to a domain, with 600,000 users and a rating of 4.7 from 12,500 reviews. It's handy for link building and for contacting editors. For outreach to UK businesses, though, the limit isn't technical. Under PECR you can email corporate bodies without prior consent, but the ICO's guidance on electronic mail marketing treats sole traders and some partnerships as individuals, who need consent, and a named work address is still personal data under the UK GDPR. Check both before writing to addresses found this way. How we build an inbound flow of enquiries instead is described on our lead generation page.
AI extensions: lots of users, low ratings
The official extensions for Claude (16 million users) and ChatGPT (6 million) have the same rating, 2.8, from 1,700 and 819 reviews. ChatGPT's now introduces itself with "Control your browser with ChatGPT": it's no longer a sidebar for writing, it's an agent that acts in the browser. That's the kind of extension that asks for broad access to the pages you open.
The UK context shows why that's worth thinking about. According to the Office for National Statistics, around 35% of businesses with 10 or more employees were using at least one AI technology in June 2026, almost three times the 12% of late 2023 (source: ONS, Artificial intelligence in UK businesses: 2023 to 2026, published 20 July 2026). The ONS doesn't break the figure down by department. In a marketing team, the person with the company's ad accounts open in the browser is often the same person who installs the AI assistant. We've ranked the AI tools that are worth paying for in our guide to the best AI tools.
The risk no list takes into account
An extension with permission to read the pages you visit can also see Google Ads, Meta Business Suite and the company CRM. In the Chrome Web Store the warning reads "Your data on all the websites you visit", and Google explains that the app or extension can "read, request or modify data from every page that you visit" (source: Chrome Web Store Help). Three documented cases show why this isn't a theoretical worry.
| Case | When | Extensions and users affected | What came out |
|---|---|---|---|
| Campaign that hit Cyberhaven | December 2024 | Over 25 extensions, over 2.3 million users | Facebook access tokens and Facebook Ads account data |
| Cluster analysed by GitLab | February 2025 | At least 16 extensions, at least 3.2 million users | Script injection for ad and SEO fraud, affiliate links |
| Study of the Chrome Web Store (AsiaCCS 2024) | June 2024 | "Security-noteworthy" extensions with almost 350 million users | 60% of extensions have never been updated |
The first case hits close to home for anyone running ads. According to LayerX's analysis, the attackers sent developers emails imitating Google warnings about alleged policy breaches, getting them to authorise an OAuth app called "Privacy Policy Extensions". With that access they uploaded malicious versions of legitimate extensions to the store, which reached users as ordinary updates. The code specifically looked for the tokens and details of Facebook Ads accounts.
The second shows a different route. According to GitLab, the person behind the campaign got access to at least some extensions directly from their original developers, without having to break into them. In practice: extensions bought or handed over, which started manipulating search results and ads after changing hands.
The overall picture isn't alarming, but it needs reading carefully. Google writes on its security blog that in 2024 less than 1% of all installs from the Chrome Web Store contained malware. On a store that, according to Chrome-Stats, holds 275,336 extensions, 1% of installs is still a large number. And the most widespread problem isn't malware but neglect: the study by Sheryl Hsu, Manda Tran and Aurore Fass found that half of the extensions with known vulnerabilities stay in the store, still vulnerable, two years after being reported.
Manifest V3: why some extensions have disappeared
There's also a technical reason why some extensions from older lists can no longer be found. Google has replaced the Manifest V2 format with V3. According to the timeline published by Chrome for Developers, from 24 July 2025, with Chrome 138, V2 extensions were disabled for everyone with no way to turn them back on, and from 31 August 2026 all the remaining ones were removed from the store. An extension that didn't move to the new format no longer exists on Chrome, while Firefox still supports V2: we checked listing by listing in our article on Firefox extensions for SEO.
Five checks before you install
- Look at the date of the last update. More than a year without updates isn't a ban, but it's a reason to look for a maintained alternative.
- Check who publishes the extension. If the developer's name is different from the one you knew, it may have been sold, as in the case GitLab described.
- Read the permissions when you install. If an extension that shows a colour asks to read every site, the request is out of proportion. Chrome disables an extension when an update adds a permission with a warning, until you accept it: don't accept it out of habit.
- Keep ad accounts in a separate Chrome profile, with as few extensions installed as possible.
- Remove anything you haven't used for a month. Every extra extension is one more supplier with access to your browser.
The same rules apply to your website: third-party plugins and integrations are the most common way in, as we explain in our guide to website security. If you want a wider choice of tools, including outside the browser, you'll find the full comparison of the best SEO tools and the one on marketing tools for small businesses.
Frequently asked questions about Chrome extensions for SEO and marketing
For on-page analysis, META SEO inspector and Detailed SEO Extension, both updated in 2026. For redirects, Redirect Path; for performance, Lighthouse. For search volumes without a subscription, Keyword Surfer. Ahrefs SEO Toolbar, MozBar and Keywords Everywhere only show their full metrics with a subscription.
In the vast majority of cases, yes: Google states that in 2024 less than 1% of installs from the Chrome Web Store contained malware. Documented cases, such as the December 2024 campaign that hit over 25 extensions and 2.3 million users while looking for Facebook Ads account data, show that it pays to check permissions, publisher and update date.
It changed its name. On the Chrome Web Store it's now called Meta Ads Data Advisor, with the same ID and 3 million users, and as well as checking the pixel it helps connect website data to Meta.
Google's Tag Assistant, together with the web tool tagassistant.google.com. Google has merged Tag Assistant Legacy and Tag Assistant Companion into a single extension, and Companion will be uninstalled automatically.
For two main reasons: the mandatory move from Manifest V2 to Manifest V3, which led to all remaining V2 extensions being removed from the store from 31 August 2026, and some extensions changing their name or owner.
One last thing that rarely gets said in this industry. In agencies and marketing teams, access reviews are done on accounts: who has the Google Ads credentials, who is an admin on the Meta page. Hardly anyone does the same for the extensions installed in the browsers of the people who use those accounts. Yet the code in the December 2024 case wasn't looking for passwords: it was looking for access tokens to Facebook Ads accounts. An inventory of the extensions in your team's browsers, repeated every six months, takes an hour and covers a way in that no password policy protects.
