Color

#3971f3

#3971f3
hex#3971f3
rgbrgb(57, 113, 243)
hslhsl(222, 89%, 59%)
oklchoklch(0.586 0.204 263.7)
Closest name: Bluetiful (#3c69e7)Relative luminance 0.1915

Colors that go with #3971f3

Charcoal, Crimson 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 →

#f3bc39

#39cef3 · #5f39f3

#f33971 · #71f339

Split-complementary

Open in tool →

#f35f39 · #cef339

#f339ce · #f3bc39 · #39f35f

Contrast

#3971f3 as textRatioAAAA largeAAAFix
Aaon white
4.35:1failpassfail
  • AA: use #306af3 as the text (4.69:1)
  • AAA: use #0d4ad9 as the text (7:1)
  • AA: or shift the background to #0a0a0a (4.55:1)
Aaon black
4.83:1passpassfail
  • AAA: use #6a94f6 as the text (7.18:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3971f3 as the background.

Brands using this color

Fonts for this mood

#3971f3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3971f3
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 #3971f3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3971f3-9ca3c4-df6e4e-211f2d-e9eff1?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