Color

#0b3589

#0b3589
hex#0b3589
rgbrgb(11, 53, 137)
hslhsl(220, 85%, 29%)
oklchoklch(0.361 0.147 262.1)
Closest name: Deep Space Royal (#223382)Relative luminance 0.0442

Colors that go with #0b3589

Charcoal, Crimson and Steel 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 →

#895f0b

#0b7489 · #200b89

#890b35 · #35890b

Split-complementary

Open in tool →

#89200b · #74890b

#890b74 · #895f0b · #0b8920

Contrast

#0b3589 as textRatioAAAA largeAAAFix
Aaon white
11.14:1passpasspassPasses AAA — no fix needed.
Aaon black
1.88:1failfailfail
  • AA: use #2f6fee as the text (4.63:1)
  • AAA: use #6896f3 as the text (7.25:1)
  • AA: or shift the background to #a6a6a6 (4.58:1)
  • AAA: or shift the background to #cfcfcf (7.15:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0b3589 as the background.

Brands using this color

Fonts for this mood

#0b3589 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0b3589
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 #0b3589 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0b3589-9ca5c4-df694e-211f2d-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