Color

#331b79

#331b79
hex#331b79
rgbrgb(51, 27, 121)
hslhsl(255, 64%, 29%)
oklchoklch(0.323 0.148 286.5)
Closest name: Deep Space Rodeo (#332277)Relative luminance 0.0287

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#62791b

#1b3279 · #621b79

#79321b · #1b7932

Split-complementary

Open in tool →

#79621b · #32791b

#791b32 · #62791b · #1b7962

Contrast

#331b79 as textRatioAAAA largeAAAFix
Aaon white
13.34:1passpasspassPasses AAA — no fix needed.
Aaon black
1.57:1failfailfail
  • AA: use #7f60dc as the text (4.61:1)
  • AAA: use #a18ae5 as the text (7.28:1)
  • AA: or shift the background to #969696 (4.51:1)
  • AAA: or shift the background to #bdbdbd (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 #331b79 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

#331b79 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #331b79
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #331b79 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/331b79-ab9cc4-dfbd4e-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