🔖 Resources
The links worth bookmarking
A short, opinionated shortlist. These are the standards I check against, the free tools I actually use, the screen readers to test with, and the best places to keep learning. Everything here is free unless noted.
Why this matters
Accessibility is still the exception, not the rule
In WebAIM's 2026 survey of the top 1,000,000 website home pages, 95.9% had detectable WCAG failures, about 56 errors per page on average. The most common problem was low-contrast text, on roughly 84% of pages. Meanwhile the WHO estimates 1 in 6 of us live with a significant disability.
Those figures come from automated testing of home pages only, which catches just part of all barriers, so the real picture is likely worse, not better. That's exactly why manual and screen-reader testing matter.
00 Our team training set
Written for our own team, and free for anyone else. Team training brings together four modules, role-based learning routes, worked cases and a planner for 30-, 60- or 90-minute sessions.
📚 Part 1: Foundations
What accessibility actually means, the seven principles of universal design with examples, and how reasonable accommodation works.
🗂️ Part 2: Standards explained
WCAG, ARIA, ATAG, EN 301 549, the ISO series, PDF/UA, ISO 21542, ADA, the EAA and the CRPD, plus how they connect and differ.
📐 Part 3: Measuring on site
Ramp slope maths, how to measure it with a level and tape, a ramp checker that draws the result and drafts the finding, the key building dimensions, and a site audit method.
🔍 The models of disability
A deep dive off part 1. The seven the profession teaches, then the wider family from moral and religious through to rights based and affirmation. One situation read nine ways, a spot-the-model exercise, and how to run it all as a sensitisation session.
🧪 Part 4: Testing what you build
A fifteen minute pass on any page, keyboard testing, real screen reader keystrokes for NVDA, VoiceOver and TalkBack, a text spacing demonstration you can switch on, what automated tools miss, and how to write a finding up.
📖 Glossary
184 plain-language terms, including disability and access needs and ISO 21542 terminology. Filter by topic, follow sources, and download or print your selection.
🧠 Knowledge check
180 questions across ten topics. Filter by question set, topic, difficulty and answer status, practise a set of ten, and download a worksheet with an optional answer key.
Make your next document accessible
Start with the format you are creating. Each guide explains what to change, why it matters and how to check the result.
Document accessibility hub
Choose a format guide and keep your findings in a document review worksheet.
Word accessibility guide
Use heading styles, real lists and simple tables. Explain images and check the file before sharing.
PDF accessibility guide
Choose the right source, correct scanned text, inspect tags and reading order, and test the final file.
PowerPoint accessibility guide
Give slides useful titles, check object order, describe visuals and prepare materials people can use.
01 Standards & guidelines
The source of truth. When in doubt, these are the last word, not a blog.
WCAG 2.2 Quick Reference (opens in a new tab)
"How to Meet WCAG", with every success criterion, its techniques and its failures, filterable by level. The page you'll return to most.
WCAG 2.2 overview (W3C) (opens in a new tab)
The plain-language introduction to what WCAG is, its levels (A/AA/AAA), and how it's versioned.
ARIA Authoring Practices (APG) (opens in a new tab)
Battle-tested patterns for menus, dialogs, tabs and more, with keyboard behaviour and code. Reach for a pattern before inventing one.
W3C WAI: Introduction (opens in a new tab)
A friendly on-ramp to web accessibility, and a good one to share with teammates and stakeholders who are new to it.
02 Testing tools
Automated tools catch only about a third of issues. Brilliant for a first pass, but no substitute for keyboard and screen-reader testing.
axe DevTools (opens in a new tab)
The most trusted automated scanner, as a browser extension. Low false positives, clear guidance. Free tier is plenty to start.
WAVE (opens in a new tab)
WebAIM's visual evaluator. It overlays icons on your page showing errors, contrast issues and structure. Great for learning to see problems.
Accessibility Insights (opens in a new tab)
Microsoft's tool. Its guided "Assessment" walks you through the manual checks automation can't do.
Lighthouse (opens in a new tab)
Built into Chrome DevTools. You get a quick accessibility score and checklist alongside performance and SEO.
Contrast checkers
Paste two colours, get AA/AAA pass or fail.
WebAIM Contrast Checker (opens in a new tab) · Our contrast guide & checker
Colour Contrast Analyser (opens in a new tab)
A desktop app with an eyedropper, so you can sample colours straight from images, PDFs and native apps.
03 Screen readers
The best way to understand accessibility is to close your eyes and listen. You already own at least one of these.
NVDA (Windows, free) (opens in a new tab)
The free, open-source screen reader most testers use on Windows. Download, press Ctrl+Alt+N, and start listening.
VoiceOver (Mac & iOS) (opens in a new tab)
Built into every Apple device. ⌘+F5 on a Mac, or triple-click the side button on iPhone.
TalkBack (Android) (opens in a new tab)
Android's built-in screen reader, and the one to use for testing how your content sounds on a phone.
Deque screen-reader shortcuts (opens in a new tab)
Printable command cheat-sheets for NVDA, JAWS and VoiceOver. Keep one open while you test.
04 Keep learning
Deeper reading, references and communities to grow with.
WebAIM (opens in a new tab)
Clear, trustworthy articles on nearly every topic, from alt text to cognitive accessibility. A gold standard since 1999.
The A11Y Project (opens in a new tab)
A community-driven checklist, posts and a big directory of tools and patterns. Approachable and practical.
web.dev: Learn Accessibility (opens in a new tab)
Google's free, structured course covering the fundamentals module by module. A great start to finish path.
MDN Accessibility (opens in a new tab)
The developer reference for accessible HTML, ARIA and CSS. Searchable, detailed and always up to date.
Deque University (opens in a new tab)
In-depth courses and reference guides from one of the industry's leading teams (some paid).
A11y Weekly (newsletter) (opens in a new tab)
A short, curated email every week, and the easiest way to keep the topic on your radar.
Prefer to learn by doing? Start with the 16 guided accessibility lessons: choose a learning path, try the examples and knowledge checks, and keep application notes in this browser. Continue with the social media guide, or bring me in to train your team.
Work with me05 The numbers, on one page
Every figure below is taught somewhere on this site, with the reasoning behind it. This is the version to print and put in a bag. Each row says where it comes from, so when somebody argues with a number you can go and read the argument rather than repeat the number.
On a screen
| What | The number | Where it is explained |
|---|---|---|
| Contrast, normal text | 4.5:1 | The ratios to hit |
| Contrast, large text | 3:1 | Large means 24px, or 18.66px bold |
| Contrast, icons, borders and focus rings | 3:1 | Non-text contrast |
| Reflow, with no sideways scrolling | 320 CSS pixels wide | Zoom, reflow and text spacing |
| Resize text | 200 percent | The plain magnification check |
| Text spacing, all four at once | line 1.5, paragraph 2em, letter 0.12em, word 0.16em | With a demonstration you can switch on |
Out on site
| What | The number | Where it is explained |
|---|---|---|
| Running slope | 1:12 maximum, 1:20 preferred | What a ramp has to do |
| Cross slope | 1:48, about 2% | The one people forget |
| Gap under a 600mm level | 50mm is 1:12, 30mm is 1:20, 12.5mm is 1:48 | Measuring with no digital level |
| Rise before a landing is needed | 500mm commonly, 760mm under the ADA | Rise per flight |
| Landing length | 1500mm, level | At the top, the bottom and between flights |
| Ramp clear width | 900mm to 1000mm | Measured between the handrails |
| Door clear width | 815mm minimum, 900mm better | Measured with the door open, not the frame |
| Turning space | 1500mm circle | Key dimensions |
| Reach range for controls | 400mm to 1200mm above the floor | Switches, handles, buttons |
| Counter or desk height | 730mm to 865mm | With knee space under it |
| Step riser | 150mm to 170mm, all equal | Steps and stairs |
| Step going | 250mm minimum, 300mm better | The depth of one tread |
| Stair comfort rule | 2R + G between 550mm and 700mm | Two risers plus one going |
These are the common international values, drawn mostly from WCAG 2.2, ISO 21542, BS 8300 and the ADA Standards. They are a working baseline and not the local building code. Confirm what is legally enforceable where you are, and say in your report which reference you measured against.
Practise, then review your own work
Use the alt-text lab to make a content decision, explore the forms and keyboard lab, then record a complete task in the digital testing worksheet.
Explore the knowledge behind the practice
Use source-linked explanations and worked examples, then create a media accessibility plan, improve content clarity, or review document publishing.
Follow the space between the measurements
Use the clear-floor and turning templates, explore reach ranges, and record walking-route measurements. Keep the approach, route connection and reference with each result.
Understand the place. Plan the improvement.
Explore mobility, sensory and cognitive access in the inclusive spaces design guide, practise with five fictional place scenarios, and carry evidence into an access project with actions, owners and follow-up.
CONTENT / TOOLS / INTERFACES / EVALUATION
Find the accessibility reference for your work
Explore WCAG for content, ATAG for authoring tools, UAAG for browsers and players, WAI-ARIA for interface semantics, ACT for test rules, and EARL for reporting results. Search the references, try practical learning activities, and follow the original sources.