Siteimprove Accessibility Checker

Name: Siteimprove Accessibility Checker
Rating: 3.4 (5 reviews)
Author: Siteimprove

Jumpstart your web accessibility efforts directly in Firefox. Is your web page accessible for everyone? Assess the accessibility of your web pages conveniently in Mozilla Firefox browser with the Siteimprove Accessibility Checker.

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Features & Capabilities

Siteimprove Accessibility Checker is a Firefox extension that lets you test any web page for accessibility against ACT rules. It provides instant analysis, a breakdown of issues, and practical recommendations linked to WCAG techniques to help you fix barriers quickly. It also securely evaluates password-protected and dynamic content, making it a practical tool for real-world sites.

By installing this extension you agree to Siteimprove's Terms of Service and Privacy Policy: Terms of Service, Privacy Policy.

User Growth & Download Statistics

Add-on Accessibility Developer Tools Privacy & Security

By:

Daily users:

Rating:

Version:

2026.3.27.678 Last updated: 2026-03-27

Version code:

6198651

Creation date:

2021-05-04

Risk:

Permissions:

Host permissions:

*://hello.siteimprove.com/*

Size:

3.13MB

Email:

su*****@siteimprove.com

URLs:

Website ,Privacy policy

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-06-19

Compare stats and ranking:

Ranking

# 2,382 ▼ 37

Other rankings

#272 in Web Development ▼ 6

#7 in effort keyword 3 ▼ 1

#8 in process keyword 52

#10 in visibility keyword 23

#14 in checker keyword 69

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Other platforms

Siteimprove Accessibility Checker (v2.0)

60,000 3.24

(25)

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

Siteimprove

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/si-accessibility-checker/

Email:

su*****@siteimprove.com

Website:

https://siteimprove.com/en/company/contact/

Permission Change History

2023-10-02: Version 2023.4.17.1160 → 2023.9.19.421

Add Host permissions: *://hello.siteimprove.com/*

Add Permissions: scripting

Remove Permissions: *://hello.siteimprove.com/*

User Reviews

by 远离*****, 2025-03-31

It is still enormously difficult to understand what I am supposed to do! You really ought to test out your system on a set of users who are not familiar with it and are not web design experts, see what they have trouble understanding, and do something about each such problem; e.g., put links into the pop-ups users get on using Siteimprove on a web page, linking to pages they can go to which will tell them what to do, with examples they can imitate E.g., when I click on the Siteimprove tool for many of my pages, one of the complaints is that the "language" is not specified. Fortunately, I found that my home page, which was designed by specialists decades ago before I knew anything about html, did not produce this complaint, and I found that it had a line <html lang="en" dir="ltr">. I guessed correctly that lang="en" specifies the language. I wasn't sure what dir="ltr" means, but I checked online and found that out; so now I know to put this on all my pages that don't have it. But your Siteimprove tool ought to give, with the diagnosis about language, a link that the user can click on and be informed of this immediately! (Maybe it does -- but if so, it's not clear where it is.) Incidentally, in addition to testing your system out on naive users, it might also be good to take a few of your workers who know the system from top to bottom, and ask them to put themselves in the place of someone naively reading the instructions, and try to note things that they might not understand. They might know subtleties of the system that naive user might incorrectly think they understood, but that they actually misunderstood. (But if it's a choice between checking it on naive users and on experts, the former seems most important.) A year ago, when these accessibility requirements were first brought to our attention, I received a long spreadsheet of problems on pages on my website. This suffered from the above difficulties, but at least it was presumably complete. This time, I don't see any way to get such a list -- do I have to go to each of the many many pages on my website and apply the Siteimprove tool to them one by one?

by Ge*****, 2025-03-09

by 敬念*****, 2025-02-12

View all user reviews ›

Is Siteimprove Accessibility Checker Safe?

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Siteimprove Accessibility Checker requires very minimum permissions.

Risk impact analysis details

Medium Access to developer tools, typically low risk unless it's used to inspect or manipulate data improperly.
Low ******* ****** ** *** ********* ******** ***************

Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Siteimprove Accessibility Checker is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Good **** ********* *** **** **** *******