Most websites have accessibility problems. Most teams aren’t catching them before launch. The good news is that the most common WCAG violations are detectable quickly — you don’t need a certified accessibility specialist to find the majority of issues.
What is WCAG?
WCAG (Web Content Accessibility Guidelines) is the international standard for website accessibility. WCAG 2.1 AA is the most widely referenced compliance level — it’s what most legal requirements reference, including ADA compliance in the US and EN 301 549 in the EU.
Meeting WCAG 2.1 AA means your site is usable by people with visual, motor, auditory, and cognitive disabilities.
The 10 most common accessibility violations
1. Missing alt text on images
Images without alt text are invisible to screen readers. Every meaningful image needs descriptive alt text. Decorative images should use alt="" to tell screen readers to skip them.
Fix: Add descriptive alt text to all non-decorative images.
2. Insufficient color contrast
Text that doesn’t have enough contrast against its background is hard to read for people with low vision or color blindness. WCAG requires 4.5:1 contrast ratio for normal text, 3:1 for large text.
Fix: Use a contrast checker to verify all text/background combinations.
3. Missing form labels
Form inputs without associated labels are unusable for screen reader users. Every input needs a visible or programmatic label (not just placeholder text).
Fix: Add <label for="input-id"> to every form input, or use aria-label.
4. Non-descriptive link text
“Click here” and “Read more” links give no context to screen reader users navigating by links. Link text should describe the destination.
Fix: Replace generic link text with descriptive text (e.g., “Read our pricing guide”).
5. Missing document language
The HTML lang attribute tells screen readers what language to use. Missing it causes pronunciation errors for screen reader users.
Fix: Add lang="en" (or the appropriate language code) to your <html> tag.
6. No skip navigation link
Keyboard-only users have to tab through the entire navigation on every page load without a skip link. This is tedious and barriers real use.
Fix: Add a “Skip to main content” link as the first focusable element on the page.
7. Missing heading hierarchy
Headings should follow a logical order (H1 → H2 → H3). Multiple H1s, or skipping from H1 to H4, makes screen reader navigation confusing.
Fix: Audit your heading structure and ensure logical hierarchy on every page.
8. No focus indicators
Users who navigate by keyboard need visible focus indicators on interactive elements. Removing the default outline without replacing it is a common accessibility failure.
Fix: Never use outline: none without providing an alternative focus style.
9. Auto-playing media
Audio or video that plays automatically is disorienting for screen reader users and people with cognitive disabilities.
Fix: Ensure all media requires user initiation to play.
10. PDF files without accessibility tagging
PDFs linked from your site should be tagged for screen reader access. Untagged PDFs are largely inaccessible.
Fix: Use tagged PDF export from Word or Acrobat, or replace PDFs with accessible HTML pages.
How to audit your site quickly
- Run an automated scan — Tools like Revanote use AI to detect the most common issues from your live site in seconds. Automated tools catch roughly 30-40% of WCAG issues.
- Keyboard navigation test — Tab through your entire site without using a mouse. Every interactive element should be reachable and visually obvious.
- Screen reader test — Use NVDA (Windows, free) or VoiceOver (Mac, built-in) to navigate your site. Listen for missing labels, confusing link text, and broken reading order.
Prioritizing fixes
Start with the issues that affect the most users and cause complete task failure:
- Missing form labels (prevents form completion)
- Color contrast failures (affects 8% of males with color blindness)
- Keyboard traps (blocks all keyboard navigation)
- Missing alt text on functional images (e.g., buttons with only icon images)
Lower severity issues like heading order and link text are still important but rarely prevent task completion entirely.
Revanote’s AI accessibility analysis flags these issues automatically, categorized by severity, pinned to the exact elements on your page — so your dev team knows exactly what to fix without a separate audit handoff.