Color

#311fa3

#311fa3
hex#311fa3
rgbrgb(49, 31, 163)
hslhsl(248, 68%, 38%)
oklchoklch(0.371 0.195 277.2)
Closest name: Depths of Night (#2c319b)Relative luminance 0.0428

Colors that go with #311fa3

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 →

#91a31f

#1f4fa3 · #721fa3

#a3311f · #1fa331

Split-complementary

Open in tool →

#a3721f · #4fa31f

#a31f4f · #91a31f · #1fa372

Contrast

#311fa3 as textRatioAAAA largeAAAFix
Aaon white
11.32:1passpasspassPasses AAA — no fix needed.
Aaon black
1.86:1failfailfail
  • AA: use #7565e2 as the text (4.72:1)
  • AAA: use #988be9 as the text (7.2:1)
  • AA: or shift the background to #a6a6a6 (4.65:1)
  • AAA: or shift the background to #cccccc (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #311fa3 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

#311fa3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #311fa3
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 #311fa3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/311fa3-a69cc4-dfac4e-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