Color

#181e63

#181e63
hex#181e63
rgbrgb(24, 30, 99)
hslhsl(235, 61%, 24%)
oklchoklch(0.282 0.12 272.1)
Closest name: Black Sea Night (#052462)Relative luminance 0.0202

Colors that go with #181e63

Charcoal, Steel Blue and Amber 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 →

#635c18

#184363 · #371863

#63181e · #1e6318

Split-complementary

Open in tool →

#633718 · #436318

#631843 · #635c18 · #186337

Contrast

#181e63 as textRatioAAAA largeAAAFix
Aaon white
14.95:1passpasspassPasses AAA — no fix needed.
Aaon black
1.4:1failfailfail
  • AA: use #636dd9 as the text (4.72:1)
  • AAA: use #888fe2 as the text (7.07:1)
  • AA: or shift the background to #8f8f8f (4.62:1)
  • AAA: or shift the background to #b3b3b3 (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #181e63 as the background.

Brands using this color

Fonts for this mood

#181e63 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #181e63
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 #181e63 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/181e63-9e9cc4-df8d4e-241f2d-e9eef1?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