Color

#0b4bcb

#0b4bcb
hex#0b4bcb
rgbrgb(11, 75, 203)
hslhsl(220, 90%, 42%)
oklchoklch(0.467 0.207 262.3)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0942

Colors that go with #0b4bcb

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 →

#cb8b0b

#0babcb · #2b0bcb

#cb0b4b · #4bcb0b

Split-complementary

Open in tool →

#cb2b0b · #abcb0b

#cb0bab · #cb8b0b · #0bcb2b

Contrast

#0b4bcb as textRatioAAAA largeAAAFix
Aaon white
7.28:1passpasspassPasses AAA — no fix needed.
Aaon black
2.88:1failfailfail
  • AA: use #2a6df4 as the text (4.59:1)
  • AAA: use #6495f7 as the text (7.18:1)
  • AA: or shift the background to #cccccc (4.54:1)
  • AAA: or shift the background to #fcfcfc (7.1:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0b4bcb as the background.

Brands using this color

Fonts for this mood

#0b4bcb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0b4bcb
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 #0b4bcb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0b4bcb-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