What the colour tools cover
The same colour can be written half a dozen ways and design tools rarely agree on which. The converters here move between HEX and RGB, HSL, CMYK, LAB and colour temperature in kelvin. The palette tools build complementary, analogous, triadic and monochromatic schemes, plus tints, shades and tones of a base colour. The contrast checker reports the WCAG 2.x ratio and pass or fail at AA and AAA, and the colour blindness simulator shows how a palette reads under the common deficiencies. CSS generators cover gradients, filters and box shadows.
Conversions between HEX, RGB and HSL are exact in both directions. Conversions that cross a gamut boundary, such as RGB to CMYK or LAB, are approximate at the edges, and the same values will look different on two uncalibrated screens. The numbers are right; the appearance is not guaranteed.
Accessibility first
- WCAG AA needs 4.5:1 for body text and 3:1 for large text and interface components. Treat a ratio between 4.4 and 4.6 as failing rather than rounding it up.
- Around 8 percent of men have some red-green colour vision deficiency. Never let colour be the only thing that carries a meaning.
- Grey text on white is the most common failure on the web and the easiest to fix.