Color

#0a3370

#0a3370
hex#0a3370
rgbrgb(10, 51, 112)
hslhsl(216, 84%, 24%)
oklchoklch(0.334 0.115 259.1)
Closest name: Atlantic Navy (#13336f)Relative luminance 0.036

Colors that go with #0a3370

Crimson, 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 →

#71470a

#0a6671 · #140a71

#710a33 · #33710a

Split-complementary

Open in tool →

#71140a · #66710a

#710a66 · #71470a · #0a7114

Contrast

#0a3370 as textRatioAAAA largeAAAFix
Aaon white
12.21:1passpasspassPasses AAA — no fix needed.
Aaon black
1.72:1failfailfail
  • AA: use #1e70eb as the text (4.57:1)
  • AAA: use #5b97f1 as the text (7.14:1)
  • AA: or shift the background to #9e9e9e (4.56:1)
  • AAA: or shift the background to #c7c7c7 (7.22:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0a3370 as the background.

Brands using this color

Fonts for this mood

#0a3370 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0a3370
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 #0a3370 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0a3370-9ca7c4-df5f4e-201f2d-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