Color

#403f5f

#403f5f
hex#403f5f
rgbrgb(64, 63, 95)
hslhsl(242, 20%, 31%)
oklchoklch(0.383 0.054 285)
Closest name: Bonne Nuit (#3a4866)Relative luminance 0.0547

Colors that go with #403f5f

Sea Green, Steel Blue and Teal 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 →

#5e5f3f

#3f4e5f · #503f5f

#5f403f · #3f5f40

Split-complementary

Open in tool →

#5f503f · #4e5f3f

#5f3f4e · #5e5f3f · #3f5f50

Contrast

#403f5f as textRatioAAAA largeAAAFix
Aaon white
10.03:1passpasspassPasses AAA — no fix needed.
Aaon black
2.09:1failfailfail
  • AA: use #7472a1 as the text (4.66:1)
  • AAA: use #9594b8 as the text (7.21:1)
  • AA: or shift the background to #b0b0b0 (4.62:1)
  • AAA: or shift the background to #d9d9d9 (7.1:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #403f5f as the background.

Brands using this color

mcpConnect your agent — build around #403f5f
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 #403f5f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/403f5f-a29cc4-df9e4e-261f2d-e9edf1?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