UI Palette Generator is a free, open-source web tool for creating interface color palettes intended for light and dark themes. Users can begin with a seed color, adjust settings, and override individual tokens. The interface reports text contrast results for WCAG 2.2 AA and APCA, but the project says people must review the output. Optional refinement actions can align semantic tokens with USWDS colors or adjust content tokens to meet WCAG 2.2 and APCA thresholds. Both themes use the same semantic token IDs, and the demo applies identical UI markup to show palette values in components. Users can download tokens as CSV, export Penpot-compatible JSON, or copy CSS variables for both themes. CSV and Penpot-compatible JSON files made by the tool can also be imported. The project uses HTML, CSS, and vanilla JavaScript; basic use needs no framework or build tools. It can run as a static site on GitHub Pages or another static web server, including by copying its docs folder to a host. The repository lists an AGPL-3.0 license and invites issue reports and contributions on GitHub.
Who it is for
This tool suits designers and developers generating accessible interface palettes for light and dark modes. It may also suit people who want CSV, Penpot-compatible JSON, or CSS variable exports.
What is good
- Generates palettes from a seed color.
- Reports WCAG 2.2 AA and APCA contrast.
- Exports CSV, Penpot-compatible JSON, and CSS variables.
- Can be self-hosted as a static site.
What to know first
- Human review is still required.
- Basic use has no framework or build tools, but no application integrations beyond listed formats are specified.
Verdict
UI Palette Generator provides palette generation, contrast reporting, and several export formats at no charge. Treat its contrast results as a review aid, not a replacement for human review.
Get started with UI Palette Generator
- Open the web tool at its website
- Choose a seed color and generate a palette
- Adjust settings or override individual tokens
- Review WCAG 2.2 AA and APCA results
- Export CSV, Penpot-compatible JSON, or CSS variables
- For self-hosting, copy the docs folder to GitHub Pages or another static server
Limits to know first
The project requires human review of palette results, including AI-assisted exploration. Basic use has no framework or build-tool requirement, but self-hosting depends on a static web server.
Questions about UI Palette Generator
Is UI Palette Generator free?
Yes. It is free, and the project is open source.
Where can it run?
It runs on the web and can be self-hosted. The static site works on GitHub Pages or any static web server.
Which contrast standards does it report?
The interface reports WCAG 2.2 AA and APCA text-contrast results.
What files can it export?
You can download CSV tokens, export Penpot-compatible JSON, or copy CSS variables for both themes.
Can existing palettes be imported?
Yes. CSV and Penpot-compatible JSON files generated by the tool can replace the displayed palette.
What license does the project use?
The public repository lists an AGPL-3.0 license.
Compared on color palette generators
- Export formats
- CSV, Penpot native JSON, CSS variables




