Color

#311f98

#311f98
hex#311f98
rgbrgb(49, 31, 152)
hslhsl(249, 66%, 36%)
oklchoklch(0.359 0.182 278.7)
Closest name: Depths of Night (#2c319b)Relative luminance 0.039

Colors that go with #311f98

Steel Blue, 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 →

#86981f

#1f4a98 · #6e1f98

#98311f · #1f9831

Split-complementary

Open in tool →

#986e1f · #4a981f

#981f4a · #86981f · #1f986e

Contrast

#311f98 as textRatioAAAA largeAAAFix
Aaon white
11.8:1passpasspassPasses AAA — no fix needed.
Aaon black
1.78:1failfailfail
  • AA: use #7562df as the text (4.57:1)
  • AAA: use #9a8de8 as the text (7.35:1)
  • AA: or shift the background to #a1a1a1 (4.57:1)
  • AAA: or shift the background to #c9c9c9 (7.12:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #311f98 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

#311f98 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #311f98
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 #311f98 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/311f98-a79cc4-dfae4e-271f2d-e9ecf1?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