Color

#3771cd

#3771cd
hex#3771cd
rgbrgb(55, 113, 205)
hslhsl(217, 60%, 51%)
oklchoklch(0.558 0.155 259.3)
Closest name: God of Rain (#4466cc)Relative luminance 0.1703

Colors that go with #3771cd

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 →

#cd9437

#37bccd · #4937cd

#cd3771 · #71cd37

Split-complementary

Open in tool →

#cd4937 · #bccd37

#cd37bc · #cd9437 · #37cd49

Contrast

#3771cd as textRatioAAAA largeAAAFix
Aaon white
4.77:1passpassfail
  • AAA: use #28569f as the text (7.19:1)
Aaon black
4.41:1failpassfail
  • AA: use #3b73ce as the text (4.53:1)
  • AAA: use #6c96da as the text (7.01:1)
  • AA: or shift the background to #fafafa (4.57:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3771cd as the background.

Brands using this color

Fonts for this mood

#3771cd reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3771cd
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 #3771cd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3771cd-9ca7c4-df624e-201f2d-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