Color

#664bbe

#664bbe
hex#664bbe
rgbrgb(102, 75, 190)
hslhsl(254, 47%, 52%)
oklchoklch(0.504 0.172 289.6)
Closest name: slateblue (#6a5acd)Relative luminance 0.1157

Colors that go with #664bbe

Charcoal, Sea Green and Amber lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#a3be4b

#4b6abe · #9f4bbe

#be664b · #4bbe66

Split-complementary

Open in tool →

#be9f4b · #6abe4b

#be4b6a · #a3be4b · #4bbe9f

Contrast

#664bbe as textRatioAAAA largeAAAFix
Aaon white
6.33:1passpassfail
  • AAA: use #5e42b8 as the text (7.13:1)
Aaon black
3.31:1failpassfail
  • AA: use #7c65c8 as the text (4.55:1)
  • AAA: use #9c8bd5 as the text (7.07:1)
  • AA: or shift the background to #dbdbdb (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #664bbe as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#664bbe reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #664bbe
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #664bbe and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/664bbe-aa9cc4-dfbb4e-291f2d-e9ebf1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md