Color Blindness Palette Fixer
Preview a palette under three color-vision simulations and explore lightness adjustments locally. This is a design aid, not a medical assessment or an accessibility guarantee. Simulations cannot describe every viewer. Use labels, patterns or shapes as well as color, and check text contrast separately.
A QUICK WALKTHROUGH
How to use this tool
- Enter 2–12 HEX colors and choose the simulation and adjustment range.
- Generate a suggestion and compare numbered swatches and all pair distances.
- Copy or download the HEX list, then review the design with labels, patterns and a separate contrast check.
Method and limits
2–12 opaque sRGB HEX colors; no names, alpha, images or uploads. Viénot protanopia/deuteranopia and Brettel tritanopia approximations run on linear sRGB, then clip and encode to 8-bit sRGB. Pair distance is RGB Euclidean distance divided by √3 × 255, expressed as a percentage. Below 12% is an arbitrary review flag, not a perceptual ΔE or WCAG threshold. “All three” uses the lowest distance across the three simulations. The suggestion searches HSL lightness offsets in 5-point steps within your limit, retaining each original hue and saturation before RGB rounding. Three ordered passes maximize each color’s minimum simulated distance to the others. This local heuristic may change brand appearance, leave close pairs, or miss better palettes; it does not certify discernibility or preserve text contrast.
GOOD TO KNOW
Common questions
Are colors uploaded?
No. Parsing, simulations and suggestions run in your browser.