Colormind
Colormind focuses on algorithmically generated palettes.
What it does
Colormind generates coordinated color combinations in one step.
When to use it
With a primary color chosen, generate alternatives for accents and test them in context.
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Color Hunt
Color Hunt focuses on community-curated four-color palettes.
Color Lisa
Color Lisa focuses on palettes inspired by artworks.
ColorHexa
ColorHexa focuses on color-code information and color relationships.