Color

#10243c

#10243c
hex#10243c
rgbrgb(16, 36, 60)
hslhsl(213, 58%, 15%)
oklchoklch(0.257 0.052 254.2)
Closest name: Dark Eclipse (#112244)Relative luminance 0.017

Colors that go with #10243c

Charcoal, Sea Green 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 →

#3c2810

#103a3c · #12103c

#3c1024 · #243c10

Split-complementary

Open in tool →

#3c1210 · #3a3c10

#3c103a · #3c2810 · #103c12

Contrast

#10243c as textRatioAAAA largeAAAFix
Aaon white
15.68:1passpasspassPasses AAA — no fix needed.
Aaon black
1.34:1failfailfail
  • AA: use #3476c5 as the text (4.54:1)
  • AAA: use #6698d6 as the text (7.03:1)
  • AA: or shift the background to #8a8a8a (4.54:1)
  • AAA: or shift the background to #b0b0b0 (7.23:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #10243c as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#10243c reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #10243c
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 #10243c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/10243c-9ca9c4-df584e-1f202d-e9f0f1?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