Color

#10339e

#10339e
hex#10339e
rgbrgb(16, 51, 158)
hslhsl(225, 82%, 34%)
oklchoklch(0.379 0.177 264.6)
Closest name: Blue Hour (#0034ab)Relative luminance 0.0495

Colors that go with #10339e

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 →

#9e7a10

#107a9e · #33109e

#9e1033 · #339e10

Split-complementary

Open in tool →

#9e3310 · #7a9e10

#9e107a · #9e7a10 · #109e33

Contrast

#10339e as textRatioAAAA largeAAAFix
Aaon white
10.56:1passpasspassPasses AAA — no fix needed.
Aaon black
1.99:1failfailfail
  • AA: use #416cec as the text (4.58:1)
  • AAA: use #7493f1 as the text (7.19:1)
  • AA: or shift the background to #ababab (4.6:1)
  • AAA: or shift the background to #d4d4d4 (7.12:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #10339e as the background.

Brands using this color

Fonts for this mood

#10339e reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #10339e
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 #10339e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/10339e-9ca1c4-df754e-221f2d-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