Color

#665bcd

#665bcd
hex#665bcd
rgbrgb(102, 91, 205)
hslhsl(246, 53%, 58%)
oklchoklch(0.542 0.17 283.5)
Closest name: slateblue (#6a5acd)Relative luminance 0.1471

Colors that go with #665bcd

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 →

#c1cd5b

#5b89cd · #9f5bcd

#cd665b · #5bcd66

Split-complementary

Open in tool →

#cd9f5b · #89cd5b

#cd5b89 · #c1cd5b · #5bcd9f

Contrast

#665bcd as textRatioAAAA largeAAAFix
Aaon white
5.33:1passpassfail
  • AAA: use #5144c5 as the text (7.04:1)
Aaon black
3.94:1failpassfail
  • AA: use #7167d0 as the text (4.55:1)
  • AAA: use #968edc as the text (7.2:1)
  • AA: or shift the background to #ededed (4.55:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #665bcd 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

#665bcd reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #665bcd
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 #665bcd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/665bcd-a59cc4-dfa74e-271f2d-e9ecf1?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