Color

#331d8c

#331d8c
hex#331d8c
rgbrgb(51, 29, 140)
hslhsl(252, 66%, 33%)
oklchoklch(0.345 0.169 282)
Closest name: Galactic Civilization (#442288)Relative luminance 0.0348

Colors that go with #331d8c

Steel Blue, Blue and Charcoal 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 →

#758c1d

#1d3e8c · #6a1d8c

#8c331d · #1d8c33

Split-complementary

Open in tool →

#8c6a1d · #3e8c1d

#8c1d3e · #758c1d · #1d8c6a

Contrast

#331d8c as textRatioAAAA largeAAAFix
Aaon white
12.39:1passpasspassPasses AAA — no fix needed.
Aaon black
1.7:1failfailfail
  • AA: use #7b62df as the text (4.65:1)
  • AAA: use #9b88e7 as the text (7.07:1)
  • AA: or shift the background to #9c9c9c (4.51:1)
  • AAA: or shift the background to #c4c4c4 (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 #331d8c as the background.

Brands using this color

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

Fonts for this mood

#331d8c reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #331d8c
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 #331d8c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/331d8c-a99cc4-dfb64e-281f2d-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