Color

#643da9

#643da9
hex#643da9
rgbrgb(100, 61, 169)
hslhsl(262, 47%, 45%)
oklchoklch(0.464 0.165 295.9)
Closest name: rebeccapurple (#663399)Relative luminance 0.0891

Colors that go with #643da9

Charcoal, Royal Blue and Sea Green 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 →

#81a93d

#3d4ba9 · #9a3da9

#a9643d · #3da964

Split-complementary

Open in tool →

#a99a3d · #4ba93d

#a93d4b · #81a93d · #3da99a

Contrast

#643da9 as textRatioAAAA largeAAAFix
Aaon white
7.55:1passpasspassPasses AAA — no fix needed.
Aaon black
2.78:1failfailfail
  • AA: use #8662c6 as the text (4.58:1)
  • AAA: use #a68bd5 as the text (7.28:1)
  • AA: or shift the background to #c9c9c9 (4.56:1)
  • AAA: or shift the background to #f7f7f7 (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #643da9 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

#643da9 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #643da9
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 #643da9 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/643da9-af9cc4-dfce4e-2a1f2d-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