axe DevTools
Deque’s extension for Chrome, Edge, and Firefox. The free version runs automated WCAG checks on one page at a time and powers many other tools. For developers and anyone comfortable in DevTools.
Get axe DevTools →Tool Shed · Accessibility
Accessibility tools
A short, curated shelf of reputable tools for making teaching and learning materials accessible. BLOOM builds accessibility in from the beginning rather than bolting it on later, and these are the free and open tools we reach for. Every entry below is genuinely free or open-source; where a tool only gives away a free tier, we say so plainly.
Start here: BLOOM’s own accessibility checker
Paste any URL and check it against WCAG with axe-core, right in your browser. Nothing leaves your device. The tools below complement it when you need to dig deeper.
Check a page
Scan a single page for accessibility problems and get plain-language explanations of what to fix. Good first stops after the BLOOM checker.
WAVE
WebAIM’s evaluation tool. Drops icons and notes right onto the page so you can see exactly where issues are. Use the web version or the browser extension. Friendly for non-developers.
Open WAVE →Accessibility Insights
Microsoft’s free, open-source extension for Chrome and Edge. Built on axe, it adds a guided manual-assessment walkthrough beyond the automated scan. For teams who want a structured review.
Get Accessibility Insights →Lighthouse
Google’s open-source auditing tool, built into Chrome DevTools. Its accessibility audit uses axe-core and gives you a quick score alongside performance and SEO. Nothing to install.
About Lighthouse →Color & contrast
Check that text and color choices are readable for people with low vision or color blindness, whether you’re building a slide deck, a handout, or a website.
WebAIM Contrast Checker
Enter a foreground and background color and see whether the contrast passes WCAG AA and AAA. The quickest sanity check for text color. Works in any browser, no install.
Open contrast checker →Colour Contrast Analyser
TPGi’s free desktop app (Windows and macOS) with an eyedropper you can point at anything on screen – PDFs, slides, images of text. Source is open on GitHub. For checking real documents, not just web colors.
Get the analyser →WhoCanUse
Shows a color pair the way people with different kinds of color blindness and low vision would actually see it, not just a pass/fail ratio. A good empathy check for designers and instructors.
Try WhoCanUse →Screen readers & testing
Automated checks catch a lot, but the surest test is using your page the way someone with a disability would. A free screen reader lets you do that.
NVDA
NV Access’s free, open-source screen reader for Windows – one of the most widely used in the world. Turn it on and listen to your own materials to find what a sighted check misses. For anyone testing real documents or sites.
Download NVDA →Learn & reference
The standards themselves, in plain language, plus tutorials and checklists to build your own understanding.
W3C WAI
The Web Accessibility Initiative is the source for WCAG. Their tutorials and “Introduction to Web Accessibility” are written for newcomers, not just engineers. The authoritative starting point.
Visit W3C WAI →WebAIM
A nonprofit at Utah State University with nearly thirty years of clear, practical articles and checklists on web accessibility. The WCAG checklist and the contrast articles are perennial favorites.
Browse WebAIM →Related communities
Talk through accessibility problems with other librarians and educators doing the same work.
Accessibility & UDL
A BLOOM community for operationalizing digital accessibility across library instruction, platforms, and services.
Visit the community →Related BLOOMs
More from BLOOM’s own repository and Tool Shed to use alongside this shelf.
Accessibility checker
Paste any URL and check it against WCAG with axe-core, right in your browser. The same checker linked at the top of this page.
Open the checker →The Worksheet Remediator
Clean up a scanned or poorly tagged worksheet so it reads correctly with a screen reader.
Open the remediator →Making Course Content Accessible with AI: Title II Readiness
A lesson on using AI to help meet the ADA Title II digital-accessibility deadline for course content.
View this lesson →Know a reputable free or open tool that belongs here? Suggest it. This shelf is maintained by the BLOOM editors.