Color

#3751d2

#3751d2
hex#3751d2
rgbrgb(55, 81, 210)
hslhsl(230, 63%, 52%)
oklchoklch(0.498 0.2 269)
Closest name: Denim (#1560bd)Relative luminance 0.1135

Colors that go with #3751d2

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.

Real palettes that use #3751d2

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#d2b837

#379ed2 · #6b37d2

#d23751 · #51d237

Split-complementary

Open in tool →

#d26b37 · #9ed237

#d2379e · #d2b837 · #37d26b

Contrast

#3751d2 as textRatioAAAA largeAAAFix
Aaon white
6.42:1passpassfail
  • AAA: use #2e48cc as the text (7.2:1)
Aaon black
3.27:1failpassfail
  • AA: use #596ed9 as the text (4.66:1)
  • AAA: use #8292e3 as the text (7.17:1)
  • AA: or shift the background to #d9d9d9 (4.55:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3751d2 as the background.

Brands using this color

Fonts for this mood

#3751d2 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3751d2
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 #3751d2 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3751d2-9c9ec4-df814e-231f2d-e9eef1?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