Color

#378dd7

#378dd7
hex#378dd7
rgbrgb(55, 141, 215)
hslhsl(208, 67%, 53%)
oklchoklch(0.627 0.138 248.2)
Closest name: Blue Jay (#5588dd)Relative luminance 0.2477

Colors that go with #378dd7

Charcoal, Crimson and Copper 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 →

#d78237

#37d7d2 · #373cd7

#d7378d · #8dd737

Split-complementary

Open in tool →

#d7373c · #d7d237

#d237d7 · #d78237 · #3cd737

Contrast

#378dd7 as textRatioAAAA largeAAAFix
Aaon white
3.53:1failpassfail
  • AA: use #2678c0 as the text (4.64:1)
  • AAA: use #1d5b91 as the text (7.1:1)
  • AA: or shift the background to #212121 (4.57:1)
Aaon black
5.95:1passpassfail
  • AAA: use #509bdc as the text (7.06:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #378dd7 as the background.

Brands using this color

Fonts for this mood

#378dd7 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #378dd7
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 #378dd7 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/378dd7-9cadc4-df4e51-1f212d-e9f1f1?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