Color

#2551cb

#2551cb
hex#2551cb
rgbrgb(37, 81, 203)
hslhsl(224, 69%, 47%)
oklchoklch(0.484 0.195 264.7)
Closest name: Denim (#1560bd)Relative luminance 0.1059

Colors that go with #2551cb

Charcoal, Sea Green and Amber 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 →

#cb9e25

#25a4cb · #4c25cb

#cb2551 · #51cb25

Split-complementary

Open in tool →

#cb4c25 · #a4cb25

#cb25a4 · #cb9e25 · #25cb4c

Contrast

#2551cb as textRatioAAAA largeAAAFix
Aaon white
6.74:1passpassfail
  • AAA: use #244ec2 as the text (7.13:1)
Aaon black
3.12:1failpassfail
  • AA: use #466edd as the text (4.53:1)
  • AAA: use #7593e6 as the text (7.07:1)
  • AA: or shift the background to #d4d4d4 (4.54:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #2551cb as the background.

Brands using this color

Fonts for this mood

#2551cb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #2551cb
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 #2551cb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/2551cb-9ca2c4-df724e-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