Color

#3740eb

#3740eb
hex#3740eb
rgbrgb(55, 64, 235)
hslhsl(237, 82%, 57%)
oklchoklch(0.494 0.249 270.7)
Closest name: C64 Blue (#003aff)Relative luminance 0.1048

Colors that go with #3740eb

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 →

#ebe237

#379aeb · #8837eb

#eb3740 · #40eb37

Split-complementary

Open in tool →

#eb8837 · #9aeb37

#eb379a · #ebe237 · #37eb88

Contrast

#3740eb as textRatioAAAA largeAAAFix
Aaon white
6.78:1passpassfail
  • AAA: use #333ceb as the text (7.03:1)
Aaon black
3.1:1failpassfail
  • AA: use #5d64ef as the text (4.53:1)
  • AAA: use #868cf3 as the text (7.06:1)
  • AA: or shift the background to #d4d4d4 (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3740eb as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#3740eb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3740eb
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 #3740eb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3740eb-9f9cc4-df924e-251f2d-e9edf1?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