Firefox extensions
Listed on Firefox Add-ons. They also install in Firefox-based browsers such as LibreWolf, Waterfox, Zen and Floorp.
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18 results
Ahrefs Free
Free website analytics, technical site audit and SEO metrics from Ahrefs for verified websites.
ARC Toolkit
Browser extension from TPGi that finds accessibility issues on individual web pages.
axe DevTools
Accessibility testing tools and browser extension from Deque, built on the axe-core rules engine.
Browserling
Online cross-browser testing service with live interactive sessions in real desktop browsers.
BuiltWith
A web tool that detects the technologies a website is built with.
Detailed SEO Extension
A free browser extension that shows a page's SEO tags, headings and links in one click.
IBM Equal Access Accessibility Checker
IBM's open-source browser extension and toolkit for automated accessibility checks of web pages.
Norton Safe Web
Free web service from Norton for looking up the safety reputation of a website.
Selenium IDE
A browser extension that records and replays interactions to build end-to-end tests for websites.
SEOquake
A free browser extension from Semrush for on-page SEO audits, link checks and page metrics.
Stark
A suite of accessibility tools for checking and fixing issues across design and development.
StatusGator
A hosted service that monitors thousands of cloud status pages and alerts teams about outages.
urlscan.io
Sandbox for the web that loads a URL and records screenshots, requests and indicators.
W3Techs Site Info
A free web lookup that shows the CMS, programming language, web server and host a site uses.
WAVE
A suite of web accessibility evaluation tools, available online and as browser extensions.
webhint
A customizable linting tool that checks websites for accessibility, speed, compatibility and security problems.
WhatRuns
A free browser extension that shows the technologies a website is built with.
WooRank
A web-based website review that audits a URL for SEO, usability and accessibility issues.
