Web Accessibility: A Practical Checklist That Goes Beyond Alt Text

The WHO estimates that roughly 16% of the global population — over 1 billion people — experience some form of disability. But the population affected by web accessibility issues is broader than people with permanent disabilities. Situational impairments affect everyone temporarily: bright sunlight making a screen hard to see (contrast matters), a broken arm making keyboard navigation necessary, a loud environment making audio inaccessible. Microsoft's inclusive design research found that a feature designed for permanent disability use cases consistently benefits users with temporary and situational limitations as well. Building accessibly isn't a niche concern — it improves the experience for a significant fraction of your actual users.

WCAG (Web Content Accessibility Guidelines) is the international standard for web accessibility, published by the W3C. It has three conformance levels: Level A (minimum), Level AA (standard target), and Level AAA (enhanced, difficult for all content). Most accessibility laws — ADA in the US, EAA in the EU, AODA in Canada — require Level AA compliance. Level AA covers perceivable (alt text, captions, sufficient contrast), operable (keyboard access, no seizure-inducing content, enough time), understandable (readable text, predictable behavior), and robust (compatible with assistive technologies). For most web applications, targeting WCAG 2.1 Level AA is the correct goal — not because of legal risk alone, but because it represents a genuinely usable experience for the widest audience.

Keyboard navigation and focus management. Many sites work fine with a mouse but are completely unusable with a keyboard alone — and keyboard navigation is required by screen readers, essential for users with motor disabilities, and used daily by many power users. Test by pressing Tab on your site and see if you can reach and activate every interactive element. Check that the focus outline is visible (don't add 'outline: none' to :focus styles without providing an alternative indicator). Ensure that modals and dropdowns trap focus when open (so Tab doesn't go behind a modal), return focus to the trigger when closed, and are dismissible with Escape. Fixing keyboard navigation typically helps the largest number of affected users with the least design disruption.