10 Common Accessibility Mistakes to Avoid

Even with the best intentions, accessibility mistakes are easy to make. Here are the 10 most common errors we see in audits — and how to fix each one.

1. Missing or Poor Alt Text

Images without alt text are invisible to screen readers. Avoid generic text like "image". Describe what the image shows and why it's there. For purely decorative images, use alt="" so screen readers skip them.

2. Insufficient Color Contrast

WCAG AA requires a minimum ratio of 4.5:1 for normal text and 3:1 for large text (18pt+ or bold 14pt+). Low contrast affects users with low vision and anyone in bright conditions.

3. Keyboard Navigation Issues

Common problems include: interactive elements unreachable via Tab, no visible focus indicator, and a tab order that doesn't follow the visual layout. All functionality must be operable via keyboard alone.

4. Missing Form Labels

Every input needs a programmatically associated label — not just placeholder text, which disappears when typing. Use <label for="..."> or aria-label. Provide clear, specific error messages when validation fails.

5. Non-Descriptive Link Text

Links that say "click here" or "read more" give no context when read out of page-flow by a screen reader. Use descriptive text: "Read our WCAG 2.2 compliance guide".

6. Inaccessible Modal Dialogs

A modal must: trap focus inside while open, be closeable via Esc, have role="dialog" with aria-labelledby, and return focus to the trigger element when closed.

7. Auto-Playing Content

Never auto-play content with audio. Always provide visible play/pause controls for videos and carousels.

8. Missing Heading Structure

Headings should form a logical hierarchy (h1 → h2 → h3). Don't skip levels. Don't use headings purely for styling — use them to describe the section that follows.

9. Time Limits Without Options

Forms or sessions with timeouts should let users extend or disable the time limit. A warning before timeout with a way to extend is required by WCAG 2.2.1.

10. PDF Files Without a Text Layer

Scanned-image PDFs are completely inaccessible to screen readers. Ensure PDFs have a proper text layer, tagged reading order, and alternative text for images.

How to Avoid These Mistakes

Regular accessibility audits are essential. Use a combination of automated tools like Toegankelijk360 AI and manual testing to catch issues early. Include people with disabilities in your testing process for real-world validation.