Resources & Tools
Professional testing options, accessibility tools, simulation software, and support organizations for people with color vision deficiency.
Professional Testing
While our online test provides a good initial screening, clinical testing with calibrated equipment provides definitive results. Here's where to get professionally tested:
Optometrist / Ophthalmologist
Your primary eye care provider can perform a comprehensive color vision evaluation using printed Ishihara plates, the Farnsworth D-15 test, or an anomaloscope. Most routine eye exams include basic color vision screening.
Ask your eye doctor about color vision testing at your next appointment.
Farnsworth D-15 Test
An arrangement test where you sort 15 colored caps in order. More precise than Ishihara for measuring severity and type. Used for occupational fitness assessments. Available at most eye care clinics.
Anomaloscope (Nagel Type)
The gold standard for color vision diagnosis. Measures the exact ratio of red and green light needed to match a reference yellow. Provides the most precise classification of type and severity. Available at specialized vision centers.
Occupational Testing
If you need color vision certification for aviation (FAA), maritime, military, or other regulated professions, you'll need testing by a certified examiner using approved methods. Contact your regulatory body for specific requirements.
Accessibility Tools
Software and hardware tools that help people with color vision deficiency navigate the digital and physical world:
Operating System Color Filters
All major operating systems include built-in color filters for color blind users:
- Windows: Settings > Ease of Access > Color Filters
- macOS: System Preferences > Accessibility > Display > Color Filters
- iOS: Settings > Accessibility > Display > Color Filters
- Android: Settings > Accessibility > Color Correction
Browser Extensions
Extensions that modify web page colors for better readability:
- Colorblindly — Chrome extension that simulates and corrects color blindness
- Color Enhancer — Chrome extension by Google that adjusts web page colors
- DaltonLens — Open-source tool for real-time color assistance
Mobile Apps
Smartphone apps for color identification and assistance:
- Color Blind Pal — Real-time camera color identification (iOS/Android)
- Color Grab — Point-and-identify color tool (Android)
- Be My Eyes — Video call with volunteers for visual assistance (iOS/Android)
Color-Correcting Glasses
Specialty eyewear that enhances color perception for some types of color blindness. Note that results vary significantly between individuals, and these do not "cure" color blindness. Popular brands include EnChroma and Pilestone. Consult an eye care professional before purchasing.
Simulation Tools
Tools that show people with normal vision what color blind people see. Useful for designers, developers, educators, and family members:
Design & Development Tools
- Chrome DevTools — Built-in vision deficiency emulation (Rendering panel > Emulate vision deficiencies)
- Figma — Built-in color blind simulation in the Accessibility plugin
- Adobe Color — Accessibility tools for checking color contrast and color blind safety
- Stark — Accessibility toolkit plugin for Figma, Sketch, and Adobe XD
Image & Photo Simulation
- Coblis — Upload images to see how they appear with different types of color blindness
- Color Oracle — Free desktop application that applies a full-screen color blind filter
Support Organizations
Colour Blind Awareness ↗
UK-based organization dedicated to raising awareness of color blindness, providing information for employers, educators, and the public.
National Eye Institute (NEI) ↗
Part of the US National Institutes of Health. Provides comprehensive, scientifically-reviewed information about color blindness and other eye conditions.
American Academy of Ophthalmology ↗
Professional organization for ophthalmologists with patient education resources about color blindness and eye health.
EnChroma ↗
Manufacturer of color-correcting eyewear. Their website includes extensive educational content about color blindness types, causes, and management.
Further Reading
Books
- "The Island of the Colorblind" by Oliver Sacks — A neurologist's exploration of a Pacific island community with high rates of achromatopsia.
- "Color Blind: A Practical Guide" — Practical advice for living and working with color vision deficiency.
- "Colour Blindness: Causes and Effects" by Donald McIntyre — Comprehensive scientific overview of color vision deficiency.
For Designers & Developers
- WCAG 2.1 Guidelines — Web Content Accessibility Guidelines include requirements for color contrast and not relying solely on color to convey information.
- "A Web for Everyone" by Sarah Horton & Whitney Quesenbery — Designing accessible web experiences, including color-blind-friendly design patterns.
- Inclusive Design Principles — Microsoft's framework for designing inclusive products and experiences.
Test Your Color Vision
Take our free 38-plate Ishihara-style test and get instant results.
Start Free Test