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Color Blindness Test

Ishihara-style plates for a quick self-check.

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Controls
Plate 1 of 5

Stylized screening, not a clinical Ishihara test.

About Color Blindness Test

An interactive color vision self-check using Ishihara-style plates — circles of colored dots with hidden numbers visible only to people with normal color vision. The test screens for the most common forms of color deficiency: protanopia (red-blind), deuteranopia (green-blind), and tritanopia (blue-blind). Results are immediate and the full test takes under two minutes.

Ishihara Plate Self-Assessment

The color blindness test uses Ishihara-style plates — circles of colored dots with a hidden number visible only to people with normal color vision. The test screens for the most common forms of color vision deficiency: protanopia (red-blind), deuteranopia (green-blind), and tritanopia (blue-blind). Sit at arm's length from the screen in normal room lighting and identify each number before advancing. The test takes under two minutes and provides an immediate indication of whether further professional assessment is warranted. Parents use it to check children before art classes or driving-age vision screenings.

Accessibility Testing for Designers

Web designers and app developers use the color blindness test to understand how color-dependent their interfaces are. After experiencing the test yourself, review your designs to ensure information is never conveyed through color alone — add icons, patterns, or text labels alongside color indicators. This is a WCAG accessibility requirement and a usability best practice. Design teams run the test during sprint reviews to build empathy for color-blind users and identify interface elements that need non-color alternatives. The test takes two minutes and can transform how your team approaches color in UI design.

Career and Driving Vision Pre-Screening

Certain careers — pilots, electricians, train operators, and military personnel — require normal color vision. Many driving authorities also test color perception during license exams. This self-assessment gives you an informal indication before the official test, reducing anxiety and helping you prepare. It is not a substitute for a professional ophthalmological evaluation, but it flags potential issues early. Students considering careers in aviation, electrical engineering, or graphic design use the test to assess suitability before investing in specialized training programs.

How to use it

  1. 01

    Open the test

    The first Ishihara plate appears immediately. No login or download required.

  2. 02

    Identify the hidden number

    Look at each plate from arm's length in normal room lighting. Type or select the number you see.

  3. 03

    Review your results

    After all plates, the tool shows which color channels may be affected and recommends next steps.

Frequently asked

The shortest path between you and the answer.

Is this a medical diagnosis?

No. This is a screening tool based on Ishihara methodology. A definitive diagnosis requires testing by an optometrist or ophthalmologist using calibrated physical plates under controlled lighting.

Does screen calibration affect results?

Yes. An uncalibrated or overly warm/cool monitor can shift the plate colors and produce inaccurate results. For the most reliable screening, reset your display to default settings and test in neutral room lighting.

Is this tool free?

Yes. Every ScreenTools.co tool is free, with no account, no paywall, and no install.

Does it work on mobile?

Yes. Layouts adapt to phone and tablet screens. Mobile Safari restricts true fullscreen, but the page fills the viewport and you can add the page to your Home Screen for an app-like experience.

Does it work offline?

Once a tool's page has loaded once, the runtime is local. A few tools that fetch fonts or icons need the first hit online; after that, refresh works offline.

Does this collect my data?

No personal data leaves your browser. The site has lightweight, privacy-respecting analytics for aggregate counts (which tool was opened) and nothing else.

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