Color

#403b5e

#403b5e
hex#403b5e
rgbrgb(64, 59, 94)
hslhsl(249, 23%, 30%)
oklchoklch(0.373 0.059 289.8)
Closest name: Call It a Night (#42364c)Relative luminance 0.0503

Colors that go with #403b5e

Steel Blue, Teal and Dark Olive 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 →

#595e3b

#3b475e · #523b5e

#5e403b · #3b5e40

Split-complementary

Open in tool →

#5e523b · #475e3b

#5e3b47 · #595e3b · #3b5e52

Contrast

#403b5e as textRatioAAAA largeAAAFix
Aaon white
10.47:1passpasspassPasses AAA — no fix needed.
Aaon black
2.01:1failfailfail
  • AA: use #776fa5 as the text (4.6:1)
  • AAA: use #9791ba as the text (7.08:1)
  • AA: or shift the background to #ababab (4.56:1)
  • AAA: or shift the background to #d4d4d4 (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 #403b5e as the background.

Brands using this color

Fonts for this mood

#403b5e reads as cool, muted, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #403b5e
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 #403b5e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/403b5e-a79cc4-dfae4e-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