Color

#183d8b

#183d8b
hex#183d8b
rgbrgb(24, 61, 139)
hslhsl(221, 71%, 32%)
oklchoklch(0.384 0.137 262.7)
Closest name: Deep Space Royal (#223382)Relative luminance 0.054

Colors that go with #183d8b

Charcoal, Steel Blue and Blue 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 →

#8c6718

#18768c · #2d188c

#8c183c · #3c8c18

Split-complementary

Open in tool →

#8c2d18 · #768c18

#8c1876 · #8c6718 · #188c2d

Contrast

#183d8b as textRatioAAAA largeAAAFix
Aaon white
10.1:1passpasspassPasses AAA — no fix needed.
Aaon black
2.08:1failfailfail
  • AA: use #3f72de as the text (4.67:1)
  • AAA: use #6f95e7 as the text (7.13:1)
  • AA: or shift the background to #adadad (4.5:1)
  • AAA: or shift the background to #d9d9d9 (7.16:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #183d8b 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

#183d8b reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #183d8b
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 #183d8b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/183d8b-9ca4c4-df6b4e-211f2d-e9eff1?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