Color

#431f9e

#431f9e
hex#431f9e
rgbrgb(67, 31, 158)
hslhsl(257, 67%, 37%)
oklchoklch(0.381 0.187 286.6)
Closest name: Galactic Civilization (#442288)Relative luminance 0.0464

Colors that go with #431f9e

Royal Blue, Blue and Crimson 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 →

#7a9e1f

#1f3b9e · #821f9e

#9e431f · #1f9e43

Split-complementary

Open in tool →

#9e821f · #3b9e1f

#9e1f3b · #7a9e1f · #1f9e82

Contrast

#431f9e as textRatioAAAA largeAAAFix
Aaon white
10.89:1passpasspassPasses AAA — no fix needed.
Aaon black
1.93:1failfailfail
  • AA: use #825ddf as the text (4.58:1)
  • AAA: use #a388e7 as the text (7.23:1)
  • AA: or shift the background to #a8a8a8 (4.58:1)
  • AAA: or shift the background to #d1d1d1 (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #431f9e as the background.

Brands using this color

Fonts for this mood

#431f9e reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #431f9e
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 #431f9e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/431f9e-ac9cc4-dfc24e-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