Color

#663d9e

#663d9e
hex#663d9e
rgbrgb(102, 61, 158)
hslhsl(265, 44%, 43%)
oklchoklch(0.458 0.152 299.9)
Closest name: rebeccapurple (#663399)Relative luminance 0.0863

Colors that go with #663d9e

Charcoal, Royal Blue and Blue 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 →

#769e3d

#3d459e · #963d9e

#9e663d · #3d9e66

Split-complementary

Open in tool →

#9e963d · #459e3d

#9e3d45 · #769e3d · #3d9e96

Contrast

#663d9e as textRatioAAAA largeAAAFix
Aaon white
7.7:1passpasspassPasses AAA — no fix needed.
Aaon black
2.73:1failfailfail
  • AA: use #8961c2 as the text (4.55:1)
  • AAA: use #a789d1 as the text (7.14:1)
  • AA: or shift the background to #c7c7c7 (4.56:1)
  • AAA: or shift the background to #f5f5f5 (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #663d9e 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

#663d9e reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #663d9e
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 #663d9e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/663d9e-b19cc4-dfd54e-2b1f2d-e9eaf1?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