Color

#031d91

#031d91
hex#031d91
rgbrgb(3, 29, 145)
hslhsl(229, 96%, 29%)
oklchoklch(0.325 0.186 264.5)
Closest name: Deepsea Kraken (#082599)Relative luminance 0.0294

Colors that go with #031d91

Crimson, Steel Blue 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 →

#917703

#036491 · #300391

#91031d · #1d9103

Split-complementary

Open in tool →

#913003 · #649103

#910364 · #917703 · #039130

Contrast

#031d91 as textRatioAAAA largeAAAFix
Aaon white
13.22:1passpasspassPasses AAA — no fix needed.
Aaon black
1.59:1failfailfail
  • AA: use #4667fb as the text (4.59:1)
  • AAA: use #7890fc as the text (7.19:1)
  • AA: or shift the background to #999999 (4.64:1)
  • AAA: or shift the background to #bdbdbd (7.04:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #031d91 as the background.

Brands using this color

Fonts for this mood

#031d91 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #031d91
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 #031d91 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/031d91-9c9fc4-df7e4e-231f2d-e9eef1?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