your colour
For any given colour you get: a base palette including the colour itself, its nearest web-safe colour, and its nearest lazy colour (#yyy shorthand); an opacity and saturation scale blended toward white and black; a full 240-colour hue spectrum; five complementary colours at hue offsets +0.25, +0.33, +0.50, +0.66 and +0.75 with opacity and saturation scales for each; and the classic 216 web-safe palette. Running continuously since 1999.
A complementary colour sits opposite your chosen colour on the colour wheel. This tool calculates five complements using hue offsets of +0.25 (quarter turn), +0.33 (third), +0.50 (true opposite), +0.66 (two-thirds) and +0.75 (three-quarter turn), giving a richer harmonic set than the single opposite most tools provide.
Web-safe colours are a palette of 216 colours built from the six RGB values 0, 51, 102, 153, 204 and 255 (hex: 00, 33, 66, 99, cc, ff), producing 6×6×6 combinations that render consistently across all displays. This tool always shows the full 216-colour web-safe palette alongside your chosen colour.
A lazy colour is a hex colour where both digits of each RGB channel are identical, allowing it to be written as a three-digit shorthand in CSS — for example #aabbcc becomes #abc. This tool finds the nearest lazy colour to any input.
The saturation scale blends your colour toward white by pushing each RGB channel toward 255. The opacity scale blends toward black by multiplying each channel toward zero. Together they give a complete tint-and-shade range for UI and web design.
Yes. Every colour has a permanent shareable URL: use ?colour=ff4500 for hex or ?r=255&g=69&b=0 for RGB. Generate a random colour with ?random=new.
v1 (1999) - pure C#, classic .NET server-side. v2r1 (2004): C# backend, JavaScript frontend; page weight dropped from ~256kb to ~24kb. v2r2 (current) — fully ported to JavaScript, retaining the original 800×600 layout.