Color

#3f7df8

#3f7df8
hex#3f7df8
rgbrgb(63, 125, 248)
hslhsl(220, 93%, 61%)
oklchoklch(0.616 0.195 262.2)
Closest name: Blue Öyster Cult (#5577ee)Relative luminance 0.225

Colors that go with #3f7df8

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 →

#f8ba3f

#3fd9f8 · #5e3ff8

#f83f7d · #7df83f

Split-complementary

Open in tool →

#f85e3f · #d9f83f

#f83fd9 · #f8ba3f · #3ff85e

Contrast

#3f7df8 as textRatioAAAA largeAAAFix
Aaon white
3.82:1failpassfail
  • AA: use #266cf7 as the text (4.59:1)
  • AAA: use #084cd4 as the text (7.01:1)
  • AA: or shift the background to #1a1a1a (4.56:1)
Aaon black
5.5:1passpassfail
  • AAA: use #6294f9 as the text (7.12:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f7df8 as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#3f7df8 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f7df8
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 #3f7df8 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f7df8-9ca5c4-df694e-211f2d-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