Best Firefox SEO extensions compared, and the one the Chrome lists tell you to install that has not been updated since 2022

If you work in Firefox, install the Detailed SEO Extension and skip SEOquake. That is the opposite of what almost every SEO extension list will tell you, and the reason is on the two listings. On addons.mozilla.org, read on 21 October 2026, Detailed SEO Extension is at version "2.2.7" and was last updated "5 months ago (May 8, 2026)". SEOquake's Firefox add-on is at version "3.9.9" and was last updated "4 years ago (Dec 22, 2022)". The Chrome build of SEOquake is a major version ahead and actively maintained. The Firefox build has been sitting still since 2022.

That is the whole point of a Firefox-specific page. A shortlist assembled from the Chrome Web Store is not transferable, because the same product name can be a current release in one store and an abandoned port in the other.

The criterion, and it is one you can check in thirty seconds

Extensions get ranked on taste constantly and it tells you nothing. The criterion here is what the add-on listing itself publishes that you can verify before you install: the publisher name, the user count, the rating with its review count, the version, and the last updated date. All five render on every Mozilla listing, free, without an account. A browser extension reads every page you visit, so the publisher identity and the maintenance date are not trivia, they are the two things that decide whether installing it is a reasonable thing to do.

The Firefox SEO catalogue as Mozilla lists it

A search for "seo" on addons.mozilla.org on 21 October 2026 reported 3,623 results. These are the first page as the store ordered them, with the figures quoted as rendered. The store writes user counts exactly rather than rounding them, which is the opposite of the Chrome Web Store, so these are unusually precise numbers for this category.

The scale difference, stated plainly

Our own Chrome page recorded the Chrome Web Store listings on 9 October 2026, where SEOquake showed 1,000,000 listed users and Detailed SEO Extension 600,000. The Firefox figures above are 13,377 and 7,761. So the Firefox SEO extension audience is roughly two orders of magnitude smaller than the Chrome one for the same two products.

That matters for a practical reason rather than a snobbish one. A small installed base means less pressure on the publisher to keep the add-on working through browser updates, and the SEOquake listing is what that looks like after four years. If you are choosing a browser to do SEO work in and you have a free choice, Chrome has the deeper toolset, and our page on which two Chrome SEO extensions to install covers that side. If Firefox is what you have, the table above is the real list.

The ranking on the stated criterion

First, Detailed SEO Extension. It is the only name in the top three that publishes a recent maintenance date, "5 months ago (May 8, 2026)", at the same version number its Chrome listing carries. Its rating is 4.3 from 23 reviews, which is a thin review count and worth knowing. It reads a single page's markup and schema, which is the job you do dozens of times a day.

Second, Ahrefs SEO Toolbar, published under "Ahrefs" with 4,960 users and a 3.3 rating. That is the lowest rating in the top five and we are not going to dress it up. It is on the list because the publisher identity is unambiguous and it is the one add-on here backed by a platform whose data you may already be paying for.

Third, SiteAnalyzer SEO Tools, at 4.8 from 829 users, the highest rating of anything on the list with a review base worth reading.

SEOquake is unranked, on the criterion, because of the 2022 date. It is the most recommended SEO extension in the world and on Firefox it has not shipped in four years. Note also the publisher string: the Firefox listing reads "SeoQuake Team" where our Chrome reading recorded "Semrush Inc." That is not an accusation of anything, it is a reason to read the publisher field before you install rather than assuming the name carries the company.

Two more publisher strings worth reading before you click. "SEO META 1 COPY" is published by "macha" and "SEO META in 1 CLICK PM" by "Jay Onion". Neither is the publisher of the original SEO META in 1 CLICK, which we wrote up separately: what the extension reports and the ten second page check it makes possible. Nothing on either listing says it is unofficial, and nothing says it is official either. The field is there to be read. We measured our own internal links on 21 October 2026 and 1,015 of our 2,598 live pages have no durable inbound link, that one included.

The three checks worth doing in the browser, whichever add-on you install

An extension is fast at exactly three things and you should not buy a crawler to do them. First, read the title tag, meta description, meta robots value and canonical on the page in front of you, because those four fields cause a surprising share of real problems. Second, read the headings in document order and see whether they describe the page or just decorate it. Third, read the structured data the page actually emits, rather than the structured data you believe your template emits. Anything that needs the whole site at once is a crawler's job.

The surface no browser extension can see

Every add-on above reads the page that is open. That is its strength and it is also its ceiling, because the page is only one of the places your buyer now ends up.

When somebody asks ChatGPT, Gemini, Perplexity, Claude or Google AI Overviews who to buy from, the answer is composed for that person at that moment and it names some businesses and not others. There is no page to open and inspect, so there is nothing for an extension to read. You can have a flawless title tag, valid schema and a canonical that is exactly right, and still not be in the answer, and no amount of reading your own markup will tell you.

AI Knows Us measures that and nothing else. We ask your buyer's question in all five apps on a schedule and record which businesses got named. From our own pricing page, read 21 October 2026: one credit is one buyer question on one app once, and "A Claude check uses 3, because Claude costs us more to run." The cheapest plan that reads all five surfaces is Growth at $299 a month, with 100 buyer questions watched and 1,200 scheduled answers a month. One credit is one buyer question, asked on one AI app, once, and a Claude check uses 3; the pricing page sets Growth at 1,200 scheduled answers a month. The $149 SEO Start tier includes no AI answer checks, so do not read it as an entry price for engine watching.

Where a rival beats us. Profound, read at tryprofound.com/pricing on 21 October 2026, publishes "Up to 9 Answer Engines tracked" on Enterprise against our five, plus "SSO/SAML + SOC 2 compliance" and "Both plans include unlimited seats". We searched our own pricing page's HTML on the same day on word boundaries and found no SSO, no SAML, no SOC 2, no ISO, no white label and no DPA in it. On engine count and on enterprise security, Profound publishes more than we do, and an extension-reading practitioner evaluating both should know that before talking to either of us.

Questions about SEO extensions in Firefox

Why do the Chrome lists not work for Firefox

Because they are lists of Chrome Web Store items. Some of those products never shipped a Firefox add-on, some shipped one and stopped maintaining it, and some are on Firefox under a different publisher name. The product name surviving the move is not the same as the product surviving it.

Is the SEOquake Firefox add-on broken

Its listing says version 3.9.9, last updated December 2022, and it still carries 13,377 users and a 4.5 rating from 159 reviews, so people are plainly using it. What we can tell you from the listing is the maintenance date, and four years is long enough that you should verify the panels you rely on still report correctly before you trust a number from it.

How many SEO extensions should I have installed

Two. One that reads a single page's markup properly and one that annotates a results page if you do that work. Past two they overlap, they all add toolbar weight, and each one is another publisher reading every page you visit.

Do these extensions report anything about AI search

Not from the page. An assistant's answer is generated per request and is not a document sitting at a URL, so there is nothing for a page-reading extension to inspect. That measurement is a different instrument entirely.

Does the user count on a Mozilla listing mean anything

It is the most honest number in the table, because Mozilla publishes it unrounded where the Chrome Web Store rounds to the nearest order of magnitude. Read it as scale rather than as a quality score, and read it next to the last updated date, which is the field that actually predicts whether the thing will work next month.