Color

#40375c

#40375c
hex#40375c
rgbrgb(64, 55, 92)
hslhsl(255, 25%, 29%)
oklchoklch(0.363 0.063 294.2)
Closest name: Call It a Night (#42364c)Relative luminance 0.046

Colors that go with #40375c

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 →

#535c37

#37415c · #53375c

#5c4137 · #375c41

Split-complementary

Open in tool →

#5c5337 · #415c37

#5c3741 · #535c37 · #375c53

Contrast

#40375c as textRatioAAAA largeAAAFix
Aaon white
10.94:1passpasspassPasses AAA — no fix needed.
Aaon black
1.92:1failfailfail
  • AA: use #7b6ca7 as the text (4.55:1)
  • AAA: use #9b8fbc as the text (7.05:1)
  • AA: or shift the background to #a8a8a8 (4.6:1)
  • AAA: or shift the background to #cfcfcf (7.02:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #40375c as the background.

Brands using this color

Fonts for this mood

#40375c reads as cool, muted, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #40375c
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 #40375c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/40375c-ab9cc4-dfbd4e-291f2d-e9ebf1?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