Color

#0a40b2

#0a40b2
hex#0a40b2
rgbrgb(10, 64, 178)
hslhsl(221, 89%, 37%)
oklchoklch(0.422 0.188 262.6)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0695

Colors that go with #0a40b2

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 →

#b27d0a

#0a94b2 · #290ab2

#b20a40 · #40b20a

Split-complementary

Open in tool →

#b2290a · #94b20a

#b20a94 · #b27d0a · #0ab229

Contrast

#0a40b2 as textRatioAAAA largeAAAFix
Aaon white
8.79:1passpasspassPasses AAA — no fix needed.
Aaon black
2.39:1failfailfail
  • AA: use #306ef3 as the text (4.65:1)
  • AAA: use #6593f6 as the text (7.06:1)
  • AA: or shift the background to #bababa (4.53:1)
  • AAA: or shift the background to #e6e6e6 (7.04:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0a40b2 as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#0a40b2 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0a40b2
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 #0a40b2 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0a40b2-9ca4c4-df6b4e-211f2d-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