Color

#381b8d

#381b8d
hex#381b8d
rgbrgb(56, 27, 141)
hslhsl(255, 68%, 33%)
oklchoklch(0.348 0.172 284.8)
Closest name: Galactic Civilization (#442288)Relative luminance 0.0355

Colors that go with #381b8d

Denim, Crimson and Royal 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 →

#718d1b

#1b388d · #711b8d

#8d381b · #1b8d38

Split-complementary

Open in tool →

#8d711b · #388d1b

#8d1b38 · #718d1b · #1b8d71

Contrast

#381b8d as textRatioAAAA largeAAAFix
Aaon white
12.28:1passpasspassPasses AAA — no fix needed.
Aaon black
1.71:1failfailfail
  • AA: use #8160e1 as the text (4.69:1)
  • AAA: use #9f87e8 as the text (7.11:1)
  • AA: or shift the background to #9e9e9e (4.59:1)
  • AAA: or shift the background to #c4c4c4 (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 #381b8d 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

#381b8d reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #381b8d
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 #381b8d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/381b8d-ab9cc4-dfbd4e-291f2d-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