Color

#183e5d

#183e5d
hex#183e5d
rgbrgb(24, 62, 93)
hslhsl(207, 59%, 23%)
oklchoklch(0.353 0.069 246.2)
Closest name: Capital Blue (#1a4157)Relative luminance 0.0443

Colors that go with #183e5d

Crimson, Royal Blue and Teal 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 →

#5d3718

#185d5a · #181c5d

#5d183e · #3e5d18

Split-complementary

Open in tool →

#5d181c · #5d5a18

#5a185d · #5d3718 · #1c5d18

Contrast

#183e5d as textRatioAAAA largeAAAFix
Aaon white
11.13:1passpasspassPasses AAA — no fix needed.
Aaon black
1.89:1failfailfail
  • AA: use #2f7ab6 as the text (4.58:1)
  • AAA: use #599dd4 as the text (7.2:1)
  • AA: or shift the background to #a6a6a6 (4.57:1)
  • AAA: or shift the background to #cfcfcf (7.15:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #183e5d 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

#183e5d reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #183e5d
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 #183e5d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/183e5d-9cadc4-df4e53-1f212d-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