Color

#10345b

#10345b
hex#10345b
rgbrgb(16, 52, 91)
hslhsl(211, 70%, 21%)
oklchoklch(0.322 0.081 253.2)
Closest name: Beyond the Stars (#0a3251)Relative luminance 0.0332

Colors that go with #10345b

Crimson, Teal 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 →

#5b3710

#105a5b · #11105b

#5b1034 · #345b10

Split-complementary

Open in tool →

#5b1110 · #5a5b10

#5b105a · #5b3710 · #105b11

Contrast

#10345b as textRatioAAAA largeAAAFix
Aaon white
12.62:1passpasspassPasses AAA — no fix needed.
Aaon black
1.66:1failfailfail
  • AA: use #2578d0 as the text (4.68:1)
  • AAA: use #5699e1 as the text (7.04:1)
  • AA: or shift the background to #9c9c9c (4.6:1)
  • AAA: or shift the background to #c2c2c2 (7.08:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #10345b as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#10345b reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #10345b
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 #10345b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/10345b-9cabc4-df534e-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