Color

#183a58

#183a58
hex#183a58
rgbrgb(24, 58, 88)
hslhsl(208, 57%, 22%)
oklchoklch(0.339 0.066 247.8)
Closest name: Maniac Mansion (#004058)Relative luminance 0.0392

Colors that go with #183a58

Crimson, Teal and Sienna 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 →

#583618

#185856 · #181a58

#58183a · #3a5818

Split-complementary

Open in tool →

#58181a · #585618

#561858 · #583618 · #1a5818

Contrast

#183a58 as textRatioAAAA largeAAAFix
Aaon white
11.76:1passpasspassPasses AAA — no fix needed.
Aaon black
1.78:1failfailfail
  • AA: use #327ab8 as the text (4.61:1)
  • AAA: use #5f9dd3 as the text (7.25:1)
  • AA: or shift the background to #a1a1a1 (4.55:1)
  • AAA: or shift the background to #c9c9c9 (7.1:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #183a58 as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Palettes built around it

Fonts for this mood

#183a58 reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #183a58
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 #183a58 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/183a58-9cadc4-df4e51-1f212d-e9f1f1?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