Color

#312db9

#312db9
hex#312db9
rgbrgb(49, 45, 185)
hslhsl(242, 61%, 45%)
oklchoklch(0.412 0.209 273.5)
Closest name: Galactic Highway (#3311bb)Relative luminance 0.0603

Colors that go with #312db9

Charcoal, Sea Green and Steel 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 →

#b4b92d

#2d6eb9 · #772db9

#b9312d · #2db931

Split-complementary

Open in tool →

#b9772d · #6eb92d

#b92d6e · #b4b92d · #2db977

Contrast

#312db9 as textRatioAAAA largeAAAFix
Aaon white
9.52:1passpasspassPasses AAA — no fix needed.
Aaon black
2.21:1failfailfail
  • AA: use #6b67da as the text (4.58:1)
  • AAA: use #8f8ce3 as the text (7.03:1)
  • AA: or shift the background to #b3b3b3 (4.54:1)
  • AAA: or shift the background to #dedede (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #312db9 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

#312db9 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #312db9
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 #312db9 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/312db9-a29cc4-df9e4e-261f2d-e9edf1?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