Color

#312fb1

#312fb1
hex#312fb1
rgbrgb(49, 47, 177)
hslhsl(241, 58%, 44%)
oklchoklch(0.407 0.197 273.9)
Closest name: Depths of Night (#2c319b)Relative luminance 0.0586

Colors that go with #312fb1

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 →

#afb12f

#2f6eb1 · #722fb1

#b1312f · #2fb131

Split-complementary

Open in tool →

#b1722f · #6eb12f

#b12f6e · #afb12f · #2fb172

Contrast

#312fb1 as textRatioAAAA largeAAAFix
Aaon white
9.67:1passpasspassPasses AAA — no fix needed.
Aaon black
2.17:1failfailfail
  • AA: use #6c6ad7 as the text (4.68:1)
  • AAA: use #908ee1 as the text (7.14:1)
  • AA: or shift the background to #b3b3b3 (4.61:1)
  • AAA: or shift the background to #dedede (7.19:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #312fb1 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

#312fb1 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #312fb1
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 #312fb1 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/312fb1-a19cc4-df9b4e-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