Website accessibility testing often focuses on screen readers and keyboard navigation—but color accessibility gets overlooked. The result? Websites that technically pass audits but fail real users. This guide walks you through testing your site specifically for color blind accessibility, from quick checks to comprehensive audits.
Why Focus on Color Blind Accessibility Testing?
When you test website accessibility for color blind visitors, you're addressing one of the most common forms of visual impairment. Unlike many accessibility issues that require specialized testing tools, color blindness problems are often visible—you just need to know how to see them.
The challenge is that color issues are context-dependent. A color combination that works fine in isolation might fail when surrounded by other interface elements. That's why testing the actual website—not just individual color swatches—matters so much.
Step 1: Quick Visual Audit
Before you open any tools, look at your website with fresh eyes and ask these questions:
Visual Audit Checklist
- Status indicators: Do error states, success messages, and warnings rely solely on color?
- Navigation: Can you identify active states without relying on color differences?
- Forms: Are required fields and validation errors marked with more than just color?
- Data visualizations: Can chart elements be distinguished without color?
- Links: Are links identifiable without relying on color alone (underlines, icons)?
Step 2: Use a Website Simulation Tool
A quick visual audit catches obvious issues, but simulation tools reveal problems you'd never spot otherwise. Our Color Blind Website Checker captures your actual live website and displays it through the eyes of users with different types of color vision deficiency.
Enter URL
Input your website address for automatic capture
View Simulations
See your site through all major CVD types
Identify Issues
Spot color combinations that cause problems
What to Look For in Simulations
When reviewing simulated views of your website, focus on:
- Elements that merge together: Buttons, links, or icons that become indistinguishable from backgrounds
- Lost information: Color-coded data that becomes a uniform blob
- Confusing states: Active/inactive states that look identical
- Hidden text: Light text on light backgrounds that was barely visible to begin with
Step 3: Check Contrast Ratios
Good contrast helps everyone, but it's especially critical for color blind users who may already struggle with color distinctions. WCAG guidelines provide specific ratios:
WCAG AA (Minimum)
- • Normal text: 4.5:1
- • Large text (18pt+): 3:1
- • UI components: 3:1
WCAG AAA (Enhanced)
- • Normal text: 7:1
- • Large text (18pt+): 4.5:1
- • Recommended for important content
Use the WCAG Contrast Checker to verify your color combinations meet these standards. Pay special attention to combinations that look fine to you but might fail for color blind users—like green text on white (common in success messages).
Step 4: Test Interactive Elements
Static pages are just the beginning. Interactive elements introduce additional color states that need testing:
Hover States
Do buttons and links change in ways that are distinguishable to color blind users? Brightness changes work better than hue shifts.
Focus States
Keyboard navigation relies on visible focus indicators. Make sure these don't depend solely on color.
Form Validation
Error and success states need more than red and green. Add icons, text, or border changes as secondary indicators.
Loading States
Progress indicators and loading animations should be visible regardless of color perception.
Step 5: Document and Prioritize Fixes
Not all accessibility issues are equally urgent. Prioritize based on:
- Critical path impact: Does the issue block key user actions like checkout or signup?
- Frequency of encounter: Is it on every page or a rarely-visited section?
- Severity: Complete invisibility vs. reduced clarity?
- Fix complexity: Quick CSS change vs. major redesign?
Common Issues You'll Find
After testing hundreds of websites for color blind accessibility, these problems appear most frequently:
Top 5 Accessibility Failures
- 1. Red/green status indicators — Success/error patterns that were designed before accessibility was considered
- 2. Colored links without underlines — Links that can't be distinguished from surrounding text
- 3. Data visualizations — Charts with too many similarly-colored data series
- 4. Form validation — Errors marked only with red borders or text color
- 5. Navigation highlights — Active states that only change hue, not brightness
Making Testing Part of Your Process
One-time testing isn't enough. Color accessibility should be part of your regular workflow:
- Design phase: Use accessible palette generators from the start
- Development: Test each feature as it's built, not just at the end
- QA: Include color blindness simulation in your testing checklist
- Launch: Final comprehensive audit before going live
- Maintenance: Re-test after any significant visual changes
Test Your Website Now
Enter your URL and see exactly how your website appears to users with color vision deficiency.