Color

#3778c8

#3778c8
hex#3778c8
rgbrgb(55, 120, 200)
hslhsl(213, 57%, 50%)
oklchoklch(0.57 0.14 255.2)
Closest name: Haddock’s Sweater (#277aba)Relative luminance 0.1842

Colors that go with #3778c8

Charcoal, Copper 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 →

#c88737

#37c1c8 · #3e37c8

#c83778 · #78c837

Split-complementary

Open in tool →

#c83e37 · #c1c837

#c837c1 · #c88737 · #37c83e

Contrast

#3778c8 as textRatioAAAA largeAAAFix
Aaon white
4.48:1failpassfail
  • AA: use #3676c4 as the text (4.62:1)
  • AAA: use #295994 as the text (7.12:1)
  • AA: or shift the background to #050505 (4.55:1)
Aaon black
4.68:1passpassfail
  • AAA: use #6799d5 as the text (7.09:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3778c8 as the background.

Brands using this color

Fonts for this mood

#3778c8 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3778c8
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 #3778c8 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3778c8-9ca9c4-df584e-1f202d-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