Color Tools (Designer-side)

Palette explorers, contrast checkers, gradient generators, and color-blindness simulators.

Designer-facing color exploration tools — distinct from the programmatic / framework-side picks in Color & Theming (culori, Radix Colors, Tailwind v4 palette).

Palette explorers / generators

★ Coolors — fast palette explorer, lock-and-spacebar workflow. Free with sign-in; ads on free tier. Closed source.
★ Realtime Colors — paste a palette, see it applied to a sample marketing page in real time. Free, closed source. The fastest way to sanity-check a palette.
Adobe Color — palette explorer with color-rules wheel and accessibility checker. Free with Adobe account.
Khroma — AI-trained on your color preferences; generates palettes. Closed source, free.
Color Hunt — curated palette gallery; free.
Paletton — old-school color-wheel tool; free.
Huemint — AI palette generator; closed source, free.
uicolors.app — Tailwind-shape scale generator. See Color & Theming.

Gradient tools

★ CSS Gradient (cssgradient.io) — straightforward gradient builder. Free.
uiGradients — curated gradient gallery; free, OSS.
Mesher / Mesh Gradient by Photo Mosh — mesh gradient generators. Free tiers.
Gradient.art — modern gradient editor; freemium.
Tailwind v4 gradients — bg-linear-to-r/oklch and friends now ship in core; usually you don't need a tool.

Contrast / accessibility

★ Stark — contrast checker, color-blindness simulator, focus-order tool; Figma / Sketch / browser plugins. Free tier covers checks; paid for full suite. Closed source.
★ WebAIM Contrast Checker — the canonical free WCAG checker. Free, no sign-in.
APCA Contrast Calculator (Myndex) — the WCAG 3 successor algorithm; free, web-based.
Polypane — closed source dev browser with built-in contrast / vision simulation; paid, free trial.
Who Can Use (whocanuse.com) — readable contrast results with vision-condition impact; free.
See Accessibility Testing for axe / Pa11y.

Color-blindness simulators

Stark — see above.
Sim Daltonism (macOS) — free OSS menubar simulator.
Coblis — free in-browser simulator.
Chrome DevTools "Rendering" panel — built-in vision simulators; free.

Color picking (in the wild)

★ ColorZilla — free browser extension; eyedropper from any web page.
Sip (macOS) — palette manager + system eyedropper; freemium.
Just Color Picker (Win/macOS) — free, closed source.
macOS Digital Color Meter — built-in; free.
EyeDropper API — new EyeDropper().open() is now baseline in Chromium browsers; build your own.

Color naming / inspiration

Name that Color — closest-named-color lookup; free, OSS.
Color Names by Meodai — open dataset of 30k+ color names.
Happy Hues — curated palettes with example UI; free.

Pick this if…

Quick palette exploration: Coolors or Khroma.
Sanity-check a palette on a real-looking page: Realtime Colors.
WCAG contrast pass/fail: WebAIM Contrast Checker.
APCA / WCAG 3: APCA Contrast Calculator.
Color-blindness audit: Stark plugin or Chrome DevTools Rendering.
Eyedrop a color from any site: ColorZilla.