9 SEO Chrome Extensions Compared for 2026

The best SEO Chrome extension for most people is a free on-page checker that needs no account: Detailed SEO Extension or SEO META in 1 CLICK. Add MozBar, SEOquake or the Ahrefs SEO Toolbar if you want authority metrics, and Keywords Everywhere if you want search volumes on the results page. None of those eight tells you whether ChatGPT, Perplexity or Google's AI Overviews can read the page you are on, which is the gap we built our own extension to fill. It is in this list, and it is labelled as ours.

Every figure below was checked on the extension's live Chrome Web Store listing on 25 October 2026 and re-checked on 1 November 2026, and the permissions come from each extension's published manifest. User counts move every week, so treat them as a size guide, not a ranking.

The nine at a glance

"The tab you click" means the extension uses Chrome's activeTab permission: it can read a page only when you press its icon. "Every site" means it has access to all websites or injects a script into every page you open. That is not a sign of bad intent, because SERP overlays and link highlighting need it, but it is the first thing to check before you install anything.

What an SEO Chrome extension should check in 2026

A good on-page extension answers the questions you would otherwise answer with View Source and a lot of scrolling:

• Title and meta description, with their lengths, because Google cuts long ones.
• Canonical and robots directives, from the meta tags and ideally the X-Robots-Tag header too, since a header noindex is invisible in the HTML.
• The heading outline: one H1, and no skipped levels.
• Links and images: internal and external counts, nofollow, and missing alt text.
• Structured data: which schema types the page declares and whether the JSON parses.
• hreflang and Open Graph for sites with language versions or social traffic.

In 2026 there is a second set of questions, because a growing share of clicks now starts in an AI answer. Can the AI search crawlers read this page under robots.txt? Does a nosnippet or max-snippet:0 directive keep it out of AI Overviews? Does the site have an llms.txt? And is the page written so a model can lift a clean answer from it? The big SEO toolbars were built before these questions mattered, and the comparison below shows it.

Free on-page checkers

Detailed SEO Extension

The default pick for a quick look at a page. One panel shows the title, meta description, robots, canonical, headings, schema, links, images and hreflang, with right-click shortcuts that open the URL in Ahrefs, Moz or Semrush. It is free with no account, installs with activeTab, and its store listing now names Ahrefs as the publisher. 600,000 users and a 4.8 rating from 233 reviews.

Missing: it does not check AI crawler access, snippet directives or llms.txt.

SEO META in 1 CLICK

The most installed of the free checkers, with 1,000,000 users and a 4.9 rating from about 1,300 reviews. It shows title and description lengths, canonical, meta robots, the H1 to H6 outline, image alt text, link counts, Open Graph and Twitter tags, and links to the site's robots.txt and sitemap. It runs on activeTab only and is on Manifest V3 (version 2.67), so articles still warning that it will stop working are out of date. Watch for the unrelated copy called "SEO META in 1 CLICK (V3)" from a different publisher.

Missing: no AI checks, and it links to robots.txt rather than reading it for you.

META SEO inspector

Strongest of the three on metadata and structured data: it lays out the full JSON-LD, all the meta tags, the heading outline, alt text and link counts, and it recently added a broken link check and a side panel. Free, with "zero account registration" in its own words. 200,000 users, 4.3 from 628 reviews.

Missing: no AI checks.

Toolbars with authority metrics

SEOquake

Semrush's extension, and the broadest free toolbar here. It adds a SEObar to every page, an overlay on Google results, an on-page audit, keyword density and a URL comparison. A free Semrush account adds Authority Score, referring domains and traffic estimates. It also shows which pages Google's AI Overviews cite for a search, which is useful SERP research, but it does not check whether your own page can be read by AI crawlers. 1,000,000 users, 3.5 from about 2,600 reviews. It runs on every site.

Ahrefs SEO Toolbar

The most useful free technical toolbar: redirect tracing, broken link checks, HTTP headers, a user-agent switcher and SERP region switching all work without paying. The headline Ahrefs metrics need a paid subscription. Its user-agent switcher includes GPTBot, ClaudeBot and PerplexityBot, so you can browse as an AI crawler, but it does not tell you whether robots.txt allows them. 400,000 users, 4.7 from 563 reviews. It runs on every site.

MozBar

The extension for Moz Domain Authority and Page Authority, overlaid on search results, plus a link highlighter, schema and hreflang views and a robots.txt and sitemap check. On-page data works in guest mode; DA and PA need a free Moz account and Spam Score needs Moz Pro. It has 900,000 users, but its rating has fallen to 1.4 from about 2,500 reviews, so read the recent reviews before relying on it.

Keyword and research extensions

Keywords Everywhere

Search volume, CPC and related keywords on Google and many other sites, with traffic estimates and Moz link metrics alongside. The free tier needs no sign-up; the volume data needs a paid plan and an API key. It is the only one of the best-known eight whose listing mentions AI at all: its free "website profiling" shows AI crawler blocking and llms.txt for every result on a Google results page. That is a research view across competitors, not a check of the page you have open. 1,000,000 users, 3.3 from about 5,700 reviews.

SEO Minion

Once a free favourite for link highlighting, broken links, an hreflang checker, a SERP preview and a location simulator. Its listing now says it is "available only to customers of Keywords Everywhere's Silver or higher plan", which many roundups have not caught up with. 200,000 users, 1.6 from 797 reviews.

The one we built: Crawl Cove SEO + AI Visibility Checker

Disclosure first: this is ours, it is new, and it is not on the Chrome Web Store yet. Until the listing is live you install it from the open-source repository with Load unpacked, which takes about a minute. It is free and MIT-licensed, it needs no account, and it runs on activeTab, so it reads a page only when you press the icon. The only requests it makes are to the site you are on: robots.txt, llms.txt and the page's own headers.

It runs the on-page checks the free tools above cover, and adds an AI answer visibility panel:

• 23 AI crawlers, allowed or blocked, read from robots.txt with the page's own path applied. They are grouped by purpose, because the purposes differ: AI search crawlers such as OAI-SearchBot and PerplexityBot decide whether you get cited, user fetchers such as ChatGPT-User open a page when someone asks about it, and training crawlers such as GPTBot and Google-Extended are an opt-out choice. Blocking GPTBot does not take you out of ChatGPT search; blocking OAI-SearchBot does. Our guide to AI crawlers in robots.txt covers which to allow.
• Snippet blocks: nosnippet or max-snippet:0 in the robots meta, the googlebot meta or the X-Robots-Tag header removes a page from AI Overviews and AI Mode as well as from its search snippet. We did not find another extension that flags these directives for that reason (checked October 2026).
• llms.txt present or missing.
• An extractability score from 0 to 100: an answer-first opening, question-shaped sections, FAQ schema, a table in structured data, and an article date and author in structured data. It is the same formula the Crawl Cove desktop app uses.

Every finding comes with its evidence and a "How to fix" link, and the report exports as Markdown for a ticket or as JSON in the open Crawl Cove export format:

Missing: no authority metrics and no keyword data. Pair it with one of the toolbars above if you need those.

Smaller extensions built only for AI visibility

Our extension is not the only one that checks AI crawlers. A wave of small, AI-only extensions appeared through 2026, and a few are worth knowing about (users as of 1 November 2026):

• AI Content Visibility Checker from Adobe (10,000 users) gives a "Citation Readability Score": how much of the page an AI agent can read.
• SAGE (3,000 users) checks robots.txt for AI bots, looks for llms.txt and llms-full.txt, and scores how readable the page is for machines.
• AI SEO Extension by RadarKit (585 users) combines an AI visibility score, an AI crawler access check and llms.txt detection.
• LLMs.txt Checker (2,000 users) does one thing: it tells you whether a site has an llms.txt or llms-full.txt.

What these do not do is the ordinary on-page SEO check, so you end up running two extensions. The difference with ours is that both halves sit in one panel, under the same check names and severities as a full site crawl.

How to choose, in one line each

• Just want to see a page's tags fast, with no account: Detailed SEO Extension or SEO META in 1 CLICK.
• Need structured data in detail: META SEO inspector.
• Need authority metrics on the SERP: MozBar for Moz DA, SEOquake for Semrush, the Ahrefs toolbar if you already pay for Ahrefs.
• Need search volume while you browse: Keywords Everywhere, on a paid plan.
• Need to know whether AI answer engines can read and quote the page: the Crawl Cove extension, or one of the AI-only checkers alongside your usual toolbar.

Two extensions cover most people: one on-page checker and one metrics toolbar. Installing five slows Chrome down and gives five extensions access to what you browse.

What an extension cannot tell you

Every extension in this list looks at one page. That is the right tool for a spot check, a competitor's page or a quick look before a client call. It is the wrong tool for the questions that cost the most traffic: which of your 400 pages carry the same broken canonical, where the orphan pages are, which redirects chain, and which pages a robots.txt rule quietly blocks from AI search crawlers across the whole site. When we tested how many UK websites block AI crawlers, 102 of the 143 sites that block GPTBot also blocked OAI-SearchBot, which takes them out of ChatGPT search answers as well as training. One page's panel shows you that for one URL; a crawl shows you every URL it applies to.

That is what a crawler does. AI visibility tracking in the Crawl Cove desktop app runs the same AI checks as the extension on every page of the site, tracks each finding from one crawl to the next, and ranks findings by impact once Search Console is connected. The extension is the spot check; the crawl is the audit.

Related

• AI crawlers in robots.txt: who to allow and block explains the difference between search, user and training crawlers.
• What is llms.txt? covers what the file is for and whether it is worth adding.
• 7 free SEO crawlers with no URL cap, reviewed is the next step up from an extension: free desktop crawlers, compared.