Charts and data visualization
Check whether series colors remain distinguishable when hue perception changes.
Color blindness simulator
Preview colors through color-vision simulations.
Paste a HEX palette or load the demo colors, then preview each swatch through protanopia, deuteranopia, tritanopia, or achromatopsia-style simulations. Hue Codex compares original and simulated colors side by side and exports a copy-ready report so you can spot hue-only risks in palettes, charts, status colors, and UI states.
Free color utility
Color Blindness
Inputs update live, exports are copy-ready, and the color math stays deterministic.
Simulation
Palette preview
Instructions
- Enter one HEX color per line, or use Demo to load a sample palette.
- Choose a simulation mode such as protanopia, deuteranopia, tritanopia, or achromatopsia.
- Review the comparison preview to see how the palette changes under the selected simulation.
- Copy the simulation report for accessibility review, palette QA, or design-system documentation.
How it fits
From color value to usable system.
Hue Codex treats each color as part of a larger workflow: conversion, accessibility, palette roles, CSS syntax, shareable URLs, and production exports.
Deterministic math
Color conversion follows CSS Color 4 conventions, including D50 Lab/LCH, D65 OKLab/OKLCH, and WCAG contrast thresholds.
Readable outputs
Every result is formatted for clear reading, project notes, documentation, and assistive technology.
Free sharing
Palette URLs can be bookmarked and sent without an account, making color decisions easy to revisit.
Quick overview
Hue Codex Color Blindness Simulator is a free browser-based tool that previews HEX palettes through protanopia, deuteranopia, tritanopia, and achromatopsia-style simulations. It compares original and simulated swatches side by side and exports a copy-ready report for accessibility review.
- Use the simulator to check whether a palette depends too heavily on hue differences.
- The tool supports protanopia, deuteranopia, tritanopia, and achromatopsia-style palette previews.
- Side-by-side swatches make it easier to spot colors that collapse into similar-looking results.
- Simulation output is a design review aid, not a substitute for contrast testing or user research.
- Pair color with labels, icons, patterns, position, or text when meaning must be understood reliably.
What the Hue Codex color blindness simulator does
The Hue Codex color blindness simulator takes a list of HEX colors and previews how those swatches may appear under common color-vision deficiency simulations. The tool shows the original and simulated swatches side by side for quick comparison.
This helps reveal when colors that look distinct in a normal palette may become difficult to tell apart for people with red-green, blue-yellow, or achromatopsia-style color perception differences.
Color blindness simulator definition
A color blindness simulator applies a color transformation to approximate how colors may appear under a color-vision deficiency, helping designers review whether color differences remain distinguishable.
Simulation modes in Hue Codex
Hue Codex provides four simulation modes for palette review. Each mode transforms the input HEX colors and displays the result next to the original swatch.
| Mode | What it approximates | What to watch for |
|---|---|---|
| Protanopia | A red-cone deficiency simulation that can make red and green distinctions less reliable. | Check warnings, errors, success colors, charts, and brand pairs that rely on red-green hue differences. |
| Deuteranopia | A green-cone deficiency simulation and another common red-green color-vision condition. | Look for palette pairs that become too similar when green information is reduced. |
| Tritanopia | A blue-cone deficiency simulation that can affect blue-yellow distinctions. | Review blue, cyan, yellow, and violet accents, especially in charts and status systems. |
| Achromatopsia | A grayscale-style simulation that removes hue information and emphasizes lightness differences. | Use it to test whether value, contrast, labels, and layout still carry meaning without color hue. |
A practical palette review workflow
Start with the palette exactly as it appears in your interface or chart. Switch through each simulation mode and look for colors that become too similar, especially when those colors communicate different states or categories.
- Paste the HEX values used by the palette, chart, or component.
- Review protanopia and deuteranopia for red-green distinction risks.
- Review tritanopia for blue-yellow and cyan-violet distinction risks.
- Review achromatopsia to see whether lightness and contrast carry enough meaning without hue.
- Add labels, icons, patterns, ordering, or text when color alone is doing important work.
- Copy the simulation report for accessibility notes, design reviews, or color-role documentation.
Best uses for a color blindness simulator
Color-vision simulation is useful whenever color communicates meaning. It is especially helpful before shipping palettes that rely on categorical hues, semantic states, or visual comparisons.
Status colors
Review error, warning, success, info, selected, and disabled states for hue-only meaning.
Brand and marketing palettes
Preview whether brand accent pairs still feel distinct under common color-vision simulations.
Design-system color roles
Document simulated colors during color-role review so teams can spot fragile color relationships early.
Simulation and accessibility caveats
Color blindness simulation is an approximation. Real color perception varies by person, display, lighting, severity, and context. A simulated preview can reveal likely risks, but it cannot prove that a palette is accessible for everyone.
Do not rely on hue alone to communicate important meaning. Use contrast, labels, icons, patterns, position, copy, and interaction states alongside color, then check important foreground/background pairs with a contrast checker.
Quick answers
Color Blindness FAQ
What is the Hue Codex color blindness simulator?
Hue Codex Color Blindness Simulator is a free browser-based tool that previews HEX palettes through protanopia, deuteranopia, tritanopia, and achromatopsia-style simulations.
Which color-vision modes does the simulator include?
The simulator includes protanopia, deuteranopia, tritanopia, and achromatopsia modes for side-by-side palette review.
What is protanopia?
Protanopia is a red-cone color-vision deficiency. In design review, it is often used to check whether red and green colors remain distinguishable enough.
What is deuteranopia?
Deuteranopia is a green-cone color-vision deficiency. It can make some red-green distinctions difficult, especially in charts and semantic UI states.
What is tritanopia?
Tritanopia is a blue-cone color-vision deficiency. It can affect blue-yellow, cyan, and violet distinctions.
What is achromatopsia mode useful for?
Achromatopsia mode gives a grayscale-style preview that helps test whether lightness, contrast, labels, and layout still communicate meaning without hue.
Can a color blindness simulator prove a palette is accessible?
No. Simulation is a helpful review tool, but accessibility also depends on contrast, context, labels, interaction states, and real user perception.
Can I copy the simulation results?
Yes. The tool exports each original HEX color with its simulated HEX result for the selected mode.