Color

#331b50

#331b50
hex#331b50
rgbrgb(51, 27, 80)
hslhsl(267, 50%, 21%)
oklchoklch(0.285 0.094 301.6)
Closest name: Fabric of Space (#341758)Relative luminance 0.0207

Colors that go with #331b50

Charcoal, Dark Olive Green and Royal 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 →

#38501b

#1b1d50 · #4e1b50

#50331b · #1b5033

Split-complementary

Open in tool →

#504e1b · #1d501b

#501b1d · #38501b · #1b504e

Contrast

#331b50 as textRatioAAAA largeAAAFix
Aaon white
14.86:1passpasspassPasses AAA — no fix needed.
Aaon black
1.41:1failfailfail
  • AA: use #8f5ec9 as the text (4.61:1)
  • AAA: use #a985d6 as the text (7.01:1)
  • AA: or shift the background to #8f8f8f (4.59:1)
  • AAA: or shift the background to #b3b3b3 (7.09:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #331b50 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

#331b50 reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #331b50
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 #331b50 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/331b50-b39cc4-dfda4e-2c1f2d-e9eaf1?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