Color

#3f58e4

#3f58e4
hex#3f58e4
rgbrgb(63, 88, 228)
hslhsl(231, 75%, 57%)
oklchoklch(0.529 0.213 269.7)
Closest name: Arcane Brew (#5260e1)Relative luminance 0.1364

Colors that go with #3f58e4

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 →

#e4cb3f

#3faae4 · #793fe4

#e43f58 · #58e43f

Split-complementary

Open in tool →

#e4793f · #aae43f

#e43faa · #e4cb3f · #3fe479

Contrast

#3f58e4 as textRatioAAAA largeAAAFix
Aaon white
5.63:1passpassfail
  • AAA: use #2944e0 as the text (7.01:1)
Aaon black
3.73:1failpassfail
  • AA: use #556be7 as the text (4.64:1)
  • AAA: use #8292ed as the text (7.28:1)
  • AA: or shift the background to #e6e6e6 (4.51:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f58e4 as the background.

Brands using this color

Fonts for this mood

#3f58e4 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f58e4
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 #3f58e4 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f58e4-9c9ec4-df834e-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