Color

#331f98

#331f98
hex#331f98
rgbrgb(51, 31, 152)
hslhsl(250, 66%, 36%)
oklchoklch(0.36 0.182 279.6)
Closest name: Depths of Night (#2c319b)Relative luminance 0.0395

Colors that go with #331f98

Steel 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 →

#84981f

#1f4898 · #701f98

#98331f · #1f9833

Split-complementary

Open in tool →

#98701f · #48981f

#981f48 · #84981f · #1f9870

Contrast

#331f98 as textRatioAAAA largeAAAFix
Aaon white
11.73:1passpasspassPasses AAA — no fix needed.
Aaon black
1.79:1failfailfail
  • AA: use #7762df as the text (4.6:1)
  • AAA: use #9888e7 as the text (7.01:1)
  • AA: or shift the background to #a1a1a1 (4.54:1)
  • AAA: or shift the background to #c9c9c9 (7.08:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #331f98 as the background.

Brands using this color

Fonts for this mood

#331f98 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #331f98
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 #331f98 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/331f98-a79cc4-dfb14e-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