Color converter
Type a color in any format — HEX, RGB, HSL, or a CSS name like tomato — and get it back in every format, ready to copy. Then check the WCAG contrast between two colors. Everything runs in your browser — nothing is uploaded.
Contrast checker (WCAG)
Check whether text is readable on its background. AA is the baseline standard; AAA is enhanced.
Color formats, briefly
HEX and RGB describe a color by its red, green, and blue channels — the same thing in two notations (an 8-digit hex or a 4th RGB value adds alpha/opacity). HSL (hue, saturation, lightness) and HSV/HSB (… value/brightness) are friendlier for picking and adjusting colors by eye. CMYK is the subtractive model used for print. This tool round-trips between all of them.
The contrast ratio ranges from 1:1 (identical) to 21:1 (black on white). WCAG asks for at least 4.5:1 for normal text and 3:1 for large text (AA), or 7:1 and 4.5:1 for the stricter AAA level. Large means roughly 18pt, or 14pt bold.