Color

#3678ce

#3678ce
hex#3678ce
rgbrgb(54, 120, 206)
hslhsl(214, 61%, 51%)
oklchoklch(0.574 0.149 256.3)
Closest name: Haddock’s Sweater (#277aba)Relative luminance 0.1867

Colors that go with #3678ce

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 →

#ce8c36

#36c4ce · #4036ce

#ce3678 · #78ce36

Split-complementary

Open in tool →

#ce4036 · #c4ce36

#ce36c4 · #ce8c36 · #36ce40

Contrast

#3678ce as textRatioAAAA largeAAAFix
Aaon white
4.44:1failpassfail
  • AA: use #3275cd as the text (4.6:1)
  • AAA: use #26599c as the text (7.02:1)
  • AA: or shift the background to #080808 (4.52:1)
Aaon black
4.73:1passpassfail
  • AAA: use #6799da as the text (7.15:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3678ce as the background.

Brands using this color

Fonts for this mood

#3678ce reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3678ce
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 #3678ce and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3678ce-9ca9c4-df5a4e-1f1f2d-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