Color

#183d67

#183d67
hex#183d67
rgbrgb(24, 61, 103)
hslhsl(212, 62%, 25%)
oklchoklch(0.356 0.084 253.6)
Closest name: Aegean Blue (#1b416f)Relative luminance 0.0451

Colors that go with #183d67

Crimson, Sea Green 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 →

#674218

#186567 · #1b1867

#67183d · #3d6718

Split-complementary

Open in tool →

#671b18 · #656718

#671865 · #674218 · #18671b

Contrast

#183d67 as textRatioAAAA largeAAAFix
Aaon white
11.04:1passpasspassPasses AAA — no fix needed.
Aaon black
1.9:1failfailfail
  • AA: use #2f78ca as the text (4.66:1)
  • AAA: use #629ada as the text (7.15:1)
  • AA: or shift the background to #a6a6a6 (4.54:1)
  • AAA: or shift the background to #cfcfcf (7.09:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #183d67 as the background.

Brands using this color

Fonts for this mood

#183d67 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #183d67
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 #183d67 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/183d67-9caac4-df564e-1f202d-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