Color Difference Checker
Enter two hex colors to see how visually different they are, from identical to very different.
Last updated: September 5, 2026
Frequently asked questions
How is color difference calculated here?
As the Euclidean distance between the two colors' red, green, and blue values, treating RGB as 3D coordinates: √((ΔR)² + (ΔG)² + (ΔB)²). It's a simple, fast measure of numerical difference.
What's the maximum possible difference?
About 441.7, which is the distance between pure black (0,0,0) and pure white (255,255,255): √(255² × 3) ≈ 441.7.
Is RGB distance the same as how different colors look to the human eye?
Not exactly - human color perception isn't uniform across RGB space (we're more sensitive to some hue differences than others), so a more accurate perceptual measure like CIE Delta E weights the components differently. RGB distance is a simpler, "good enough" approximation for most everyday comparisons.
Can I use this to check if two brand colors are too similar?
Yes, as a rough check - a low RGB distance (under about 30) suggests colors that could be hard to tell apart, useful for flagging potential branding or accessibility conflicts before a more rigorous perceptual check.
Does color order matter - is comparing Color 1 to Color 2 the same as Color 2 to Color 1?
No, the result is identical either way. Euclidean distance is symmetric, so swapping which hex code goes in which box doesn't change the calculated difference.
What's the difference between #FF0000 (red) and #00FF00 (green) using this calculator?
About 360.6. Red is (255,0,0) and green is (0,255,0), so the distance is √(255² + 255² + 0²) ≈ 360.6 - close to the maximum, reflecting how visually distinct the two colors are.
Is this the same thing as a 'color contrast checker' for accessibility?
No - contrast checkers for WCAG accessibility measure luminance contrast (important for text readability), while this tool measures raw RGB distance between two colors. A pair of colors can have a large RGB distance but still fail a luminance contrast test, or vice versa.