Color

#310d77

#310d77
hex#310d77
rgbrgb(49, 13, 119)
hslhsl(260, 80%, 26%)
oklchoklch(0.303 0.158 287.9)
Closest name: Galactic Federation (#330077)Relative luminance 0.0227

Colors that go with #310d77

Charcoal, Cobalt 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 →

#54770d

#0d1f77 · #660d77

#77310d · #0d7731

Split-complementary

Open in tool →

#77660d · #1f770d

#770d1f · #54770d · #0d7766

Contrast

#310d77 as textRatioAAAA largeAAAFix
Aaon white
14.44:1passpasspassPasses AAA — no fix needed.
Aaon black
1.45:1failfailfail
  • AA: use #8755ec as the text (4.54:1)
  • AAA: use #a883f1 as the text (7.18:1)
  • AA: or shift the background to #919191 (4.58:1)
  • AAA: or shift the background to #b5b5b5 (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 #310d77 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

#310d77 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #310d77
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 #310d77 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/310d77-ae9cc4-dfc94e-2a1f2d-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