Color

#643b6d

#643b6d
hex#643b6d
rgbrgb(100, 59, 109)
hslhsl(289, 30%, 33%)
oklchoklch(0.422 0.094 320.2)
Closest name: Heartless (#623b70)Relative luminance 0.0694

Colors that go with #643b6d

Charcoal, Sea Green and Crimson 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.

Real palettes that use #643b6d

Tints & shades

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

Harmonies

Complementary

Open in tool →

#446d3b

#4b3b6d · #6d3b5d

#6d643b · #3b6d64

Split-complementary

Open in tool →

#5d6d3b · #3b6d4b

#6d4b3b · #446d3b · #3b5d6d

Contrast

#643b6d as textRatioAAAA largeAAAFix
Aaon white
8.79:1passpasspassPasses AAA — no fix needed.
Aaon black
2.39:1failfailfail
  • AA: use #9a5da8 as the text (4.51:1)
  • AAA: use #b588bf as the text (7.24:1)
  • AA: or shift the background to #bababa (4.53:1)
  • AAA: or shift the background to #e6e6e6 (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 #643b6d as the background.

Brands using this color

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

mcpConnect your agent — build around #643b6d
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 #643b6d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/643b6d-be9fc1-a8cb62-2d1f2a-ece9f1?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