color-hash

ColorHash is a lightweight Python library for generating deterministic colors from objects' string representations.

By calculating a color value based on an object's hash, it ensures consistent results: the same input will always yield the same color. This is particularly useful for UI elements like user avatars or category labels where visual consistency is required.

This module is a port of the original color-hash Javascript library.

Key features:

• Deterministic: Same input always results in the same color.
• Customizable: Influence hue range, lightness, and saturation.
• No runtime dependencies: Lightweight and easy to integrate.
• Compatibility: Supports Python 3.8–3.15.

Quick Start

>>> from colorhash import ColorHash
>>> c = ColorHash('Hello World')
>>> c.hsl
(131, 0.65, 0.5)
>>> c.rgb
(45, 210, 75)
>>> c.hex
'#2dd24b'

Installation

It is available on PyPI.

pip install colorhash

Basic (intended) use

code	hex	color
ColorHash('hey')	#782d86
ColorHash('oh')	#d29d79
ColorHash('boi')	#6ce072

Advanced usage

You can influence every aspect of final color. Default values are following:

ColorHash(
    obj: Any,
    lightness: Union[int, float, Sequence[Union[int, float]]] = (0.35, 0.5, 0.65),  # picks deterministically one
    saturation: Union[int, float, Sequence[Union[int, float]]] = (0.35, 0.5, 0.65),  # picks deterministically one
    min_h: Optional[int] = None,  # hue, min 0
    max_h: Optional[int] = None,  # hue, max 360
)

But be careful, setting tight conditions may result in very similar colors. See example tables.

You can fix lightness or saturation to single value(s) by using sequence with 1 element (eg. [0.5]). Providing more values enables wider variety of options for ColorHash to choose from (deterministically).

Note: If you provide a single integer or float instead of a sequence, it will be automatically wrapped in a list for convenience.

code	hex	color
ColorHash('hey', lightness=[0.55])	#b453c6
ColorHash('hey', lightness=[0.75])	#d69fdf
ColorHash('hey', lightness=[0.95])	#f7ecf9
ColorHash('hey', saturation=[0.15])	#8d6c93
ColorHash('hey', saturation=[0.55])	#b139c6
ColorHash('hey', saturation=[0.95])	#d406f9
ColorHash('hey', lightness=[0.95], saturation=[0.95])	#fbe6fe
ColorHash('oh', lightness=[0.95], saturation=[0.95])	#fef0e6
ColorHash('boi', lightness=[0.95], saturation=[0.95])	#e6fee7

You can set hue range or even fix it by setting min_h = max_h. If only min_h is set, max_h defaults to 360; if only max_h is set, min_h defaults to 0. When either bound is set, the hash selects one of 359 evenly spaced hue values across the inclusive range. Hue is measured in degrees. Hue values of 0° and 360° represent the same point on the hue circle and produce identical RGB values.

code	hex	color
ColorHash('hey', min_h=150)	#862d67
ColorHash('hey', min_h=300)	#862d3d
ColorHash('hey', max_h=150)	#2d862f
ColorHash('hey', min_h=150, max_h=360)	#862d67
ColorHash('hey', min_h=120, max_h=120) # fixed green hue	#2d862d
ColorHash('hey mama', min_h=120, max_h=120) # fixed green hue	#53ac53

Or you can let ColorHash decide between combination of many lightness and saturation options (mind min_h and max_h are equal in this example).

code	hex	color
ColorHash('stick', min_h=65, max_h=65, saturation=[x/10 for x in range(1, 10)], lightness=[x/10 for x in range(1, 10)])	#869108
ColorHash('with', min_h=65, max_h=65, saturation=[x/10 for x in range(1, 10)], lightness=[x/10 for x in range(1, 10)])	#eef5a3
ColorHash('one', min_h=65, max_h=65, saturation=[x/10 for x in range(1, 10)], lightness=[x/10 for x in range(1, 10)])	#ddeb47

Finally some bad examples. When you set too strict rules, colors may be almost identical.

code	hex	color
ColorHash('lets', lightness=[0.95], saturation=[0.95], min_h=300)	#fee6ed
ColorHash('break', lightness=[0.95], saturation=[0.95], min_h=300)	#fee6f6
ColorHash('it', lightness=[0.95], saturation=[0.95], min_h=300)	#fee6f3
ColorHash('here', min_h=150, max_h=150)	#6ce0a6
ColorHash('goes', min_h=150, max_h=150)	#79d2a6
ColorHash('color', min_h=150, max_h=150)	#6ce0a6

Hue mapping change in version 3.0.0

Version 2.x.x mapped a bounded hue range using only part of the requested interval (🐛). Version 3 fixes it and maps the hash across the full inclusive interval. Colors can change when the resulting interval has a nonzero width. Calls without hue bounds and calls with a fixed hue retain their previous colors.

Call	Version 2.x.x	Version 3.0.0
ColorHash('hey', min_h=150)	#2d5886	#862d67
ColorHash('hey')	#782d86	#782d86
ColorHash('hey', min_h=150, max_h=150)	#2d8659	#2d8659

Changelog

• color-hash 3.0.0 (unreleased)
  • 🐛 Fixed hue range mapping: when min_h and/or max_h is supplied, hashes now span the full inclusive interval.
  • 💥 BREAKING CHANGE: Colors may differ from version 2.x.x when min_h or max_h is provided.
• color-hash 2.3.0 (2026-03-13)
  • ⚡️ Refactor for better performance
• color-hash 2.2.1 (2026-03-12)
  • ⏪ Reverts a hue calculation change in 2.2.0, which is how it should be, but produces different colors then up until now
• color-hash 2.2.0 (2026-03-12) (YANKED)
  • 🐛 Fixed hue calculation range mapping to correctly use the full spectrum when min_h and max_h are provided.
  • ✨ Support up to python3.15 (tested on 3.15.0a6).
  • ⚰️ python3.7 does not work any more for sure.
• color-hash 2.1.0 (2025-06-17)
  • ✨ Support up to python3.14.
  • ✨ Use uv.
  • ⚰️ python3.7 is still supported and might work, but not tested any more.
• color-hash 2.0.0 (2023-09-22)
  • ✨ Expose params to influence colors.
  • ✨ Runtime validation of input params.
  • 📝 Update docs for advanced usage.
• color-hash 1.3.2 (2023-09-21)
  • ⚡️ 30%+ speedup on hsl2rgb().
  • ✅ Add tests for all named colors (1500+ tests).
• color-hash 1.3.1 (2023-09-21)
  • 🐛 Handle missing importlib-metadata import.
• color-hash 1.3.0 (2023-09-20)
  • 🧑‍💻 Add py.typed to support type annotations (#4).
  • 📦 Changed packaging ecosystem.
    • ➖ Remove poetry.
    • ➖ Remove tox.
    • ➕ Add pip-tools (manage dependencies).
    • ➕ Add hatch (build & test).
    • ➕ Add twine (publish).
  • ✨ Support python3.11.
  • ⚰️ Drop support for python3.6 (downloads from PyPI are under 1%).
• color-hash 1.2.2 (2022-10-17)
  • ✨ Add publish helper script.
• color-hash 1.2.1 (2022-10-17)
  • 📝 Update docs.
• color-hash 1.2.0 (2022-10-17)
  • 🧑‍💻 Use typing supporting python3.6.
• color-hash 1.1.0 (2022-09-01)
  • ✅ Add tests.
  • 🚸 Add installation instructions.
• color-hash 1.0.4 (2021-11-30)
  • 🐍 Support only for python3.6+.
  • ✅ Add tests.
• color-hash 1.0.3 (2020-12-04)
  • ⚰️ Drop support for python2.x.
  • 🎉 Handover of project maintenance.
• color-hash 1.0.2 (2016-07-08)
  • ✨ Add crc32_hash function and set default hashfunc to that. It's not fully backwards-compatible, but I don't want to bump the version a lot for not doing my research.
• color-hash 1.0.0 (2016-07-07)
  • 🎉 Initial port.

License

Copyright (c) 2016 Felix Krull f_krull@gmx.de

This is a port of the 'color-hash' Javascript library which is:

Copyright (c) 2015 Zeno Zeng

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.