Color

#181f7b

#181f7b
hex#181f7b
rgbrgb(24, 31, 123)
hslhsl(236, 67%, 29%)
oklchoklch(0.31 0.152 270.4)
Closest name: midnightblue (#191970)Relative luminance 0.026

Colors that go with #181f7b

Steel Blue, Blue and Charcoal 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 →

#7b7518

#18517b · #43187b

#7b181f · #1f7b18

Split-complementary

Open in tool →

#7b4318 · #517b18

#7b1851 · #7b7518 · #187b43

Contrast

#181f7b as textRatioAAAA largeAAAFix
Aaon white
13.81:1passpasspassPasses AAA — no fix needed.
Aaon black
1.52:1failfailfail
  • AA: use #616ae0 as the text (4.65:1)
  • AAA: use #888ee7 as the text (7.07:1)
  • AA: or shift the background to #949494 (4.55:1)
  • AAA: or shift the background to #bababa (7.11:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #181f7b as the background.

Brands using this color

Fonts for this mood

#181f7b reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #181f7b
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 #181f7b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/181f7b-9e9cc4-df8f4e-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