Color Palette Generator: text, image, harmony and WCAG

Turn a single color, a few words, or an image into a full color palette. Every palette comes back with hex, RGB and HSL values, plain-English color names, WCAG contrast grades, and copy-paste code for CSS, SCSS and Tailwind.

It runs fully offline. No third-party color API, no API key, nothing to rate-limit or break. The only time it touches the network is when you hand it an image URL to read colors from.

What you can feed it

Put one item per line in Colors, themes, or image URLs. The Actor detects what each line is:

• A hex color like #2E86DE or 2E86DE. It builds a harmony around that exact color.
• A theme in words like sunset, dark forest, corporate, cyberpunk neon. Known themes map to hand-picked bases; anything else gets a stable palette derived from the words, so the same phrase always returns the same colors.
• A public image URL. The Actor pulls the dominant colors and also suggests a harmony built from the main one.

What you get back

Each palette is one dataset item:

• colors: the swatches, each with hex, rgb, hsl, a readable name, luminance, the bestTextColor to place on top, and wcag grades against white and black.
• baseColor, scheme, and temperature (warm, cool, or neutral).
• exports: ready-to-paste hexList, css variables, scss variables, and a tailwind config block.
• allSchemes: the hex list for all nine harmony schemes, when you leave that option on.
• For image queries: proportion on each color and a suggestedHarmony.

Harmony schemes

Complementary, analogous, triadic, split complementary, tetradic, square, monochromatic, shades, and tints. Leave Harmony scheme on Auto and each query gets a fitting one, or force a single scheme for every query.

Example input

{
  "queries": ["#2E86DE", "sunset", "dark forest", "https://example.com/photo.jpg"],
  "scheme": "auto",
  "includeAllSchemes": true,
  "colorsPerImage": 6
}

Why the contrast grades matter

Picking colors is easy; picking colors people can actually read is the hard part. Each swatch is scored with the WCAG 2.1 contrast formula against both white and black text, graded AAA, AA, AA Large, or Fail, so you know at a glance which colors work for body text and which are decoration only.

Notes

Color naming is algorithmic (hue, lightness and saturation bands), so it stays consistent and never depends on an outside lookup service. Image reading downsamples the picture and clusters its pixels, which keeps runs fast and cheap.