Color

#403b63

#403b63
hex#403b63
rgbrgb(64, 59, 99)
hslhsl(248, 25%, 31%)
oklchoklch(0.376 0.068 288.4)
Closest name: Black Turmeric (#2c4364)Relative luminance 0.0512

Colors that go with #403b63

Steel Blue, Teal 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 →

#5e633b

#3b4a63 · #543b63

#63413b · #3b6341

Split-complementary

Open in tool →

#63543b · #4a633b

#633b4a · #5e633b · #3b6354

Contrast

#403b63 as textRatioAAAA largeAAAFix
Aaon white
10.38:1passpasspassPasses AAA — no fix needed.
Aaon black
2.02:1failfailfail
  • AA: use #7770a9 as the text (4.67:1)
  • AAA: use #9893be as the text (7.25:1)
  • AA: or shift the background to #ababab (4.52:1)
  • AAA: or shift the background to #d4d4d4 (7:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #403b63 as the background.

Brands using this color

mcpConnect your agent — build around #403b63
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 #403b63 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/403b63-a69cc4-dfac4e-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