Color

#10404c

#10404c
hex#10404c
rgbrgb(16, 64, 76)
hslhsl(192, 65%, 18%)
oklchoklch(0.346 0.054 218.1)
Closest name: Cold and Dark (#154250)Relative luminance 0.043

Colors that go with #10404c

Crimson, Steel 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 →

#4c1c10

#104c3a · #10224c

#4c1040 · #404c10

Split-complementary

Open in tool →

#4c1022 · #4c3a10

#3a104c · #4c1c10 · #224c10

Contrast

#10404c as textRatioAAAA largeAAAFix
Aaon white
11.29:1passpasspassPasses AAA — no fix needed.
Aaon black
1.86:1failfailfail
  • AA: use #208097 as the text (4.6:1)
  • AAA: use #29a3c2 as the text (7.11:1)
  • AA: or shift the background to #a6a6a6 (4.64:1)
  • AAA: or shift the background to #cccccc (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #10404c as the background.

Brands using this color

Fonts for this mood

#10404c reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #10404c
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 #10404c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/10404c-a2b5be-df4e77-1f242d-e9f1ef?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