Color

#665bbe

#665bbe
hex#665bbe
rgbrgb(102, 91, 190)
hslhsl(247, 43%, 55%)
oklchoklch(0.532 0.15 285.1)
Closest name: slateblue (#6a5acd)Relative luminance 0.1402

Colors that go with #665bbe

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 →

#b2be5b

#5b81be · #985bbe

#be665b · #5bbe66

Split-complementary

Open in tool →

#be985b · #81be5b

#be5b81 · #b2be5b · #5bbe98

Contrast

#665bbe as textRatioAAAA largeAAAFix
Aaon white
5.52:1passpassfail
  • AAA: use #5447b3 as the text (7.17:1)
Aaon black
3.8:1failpassfail
  • AA: use #7469c3 as the text (4.55:1)
  • AAA: use #968ed2 as the text (7.1:1)
  • AA: or shift the background to #e8e8e8 (4.5:1)

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

Brands using this color

Fonts for this mood

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

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

tool url/palettes/new/665bbe-a59cc4-dfaa4e-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