colortools-cx

Tiny, zero-dependency color utilities for Python: convert HEX/RGB to OKLCH, HSL, HSV, CMYK and check WCAG contrast — the same math that powers the free color picker and color converter at colorpicker.cx.

Install

pip install colortools-cx

Usage

from colortools_cx import hex_to_oklch, format_oklch, to_all_formats, contrast_ratio

format_oklch(hex_to_oklch("#ff0000"))
# 'oklch(62.8% 0.2577 29.23)'

to_all_formats("#5B7CFA")
# {'hex': '#5B7CFA', 'rgb': 'rgb(91, 124, 250)',
#  'hsl': 'hsl(227.55, 94.08%, 66.86%)', 'hsv': 'hsv(227.55, 63.6%, 98.04%)',
#  'cmyk': 'cmyk(63.6%, 50.4%, 0%, 1.96%)', 'oklch': 'oklch(62.74% 0.191 269.21)'}

contrast_ratio("#FDF0D5", "#003049")
# 12.25  (passes WCAG AA & AAA)

API

• hex_to_oklch(hex) -> {l, c, h}
• rgb_to_oklch(r, g, b) -> {l, c, h}
• format_oklch({l, c, h}) -> CSS oklch() string
• to_all_formats(hex) -> {hex, rgb, hsl, hsv, cmyk, oklch}
• contrast_ratio(fg, bg) -> WCAG 2.1 ratio (1-21)
• parse_hex(hex) -> (r, g, b) or (r, g, b, a)

Interactive version

Pick colors from an image, build palettes and CSS gradients, and check contrast in the browser at colorpicker.cx — free, no signup.

License

MIT (c) ColorTools