Color

#3f74ab

#3f74ab
hex#3f74ab
rgbrgb(63, 116, 171)
hslhsl(211, 46%, 46%)
oklchoklch(0.548 0.103 251)
Closest name: Blue Triumph (#4376ab)Relative luminance 0.1649

Colors that go with #3f74ab

Charcoal, Sea Green and Sienna 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 →

#ab773f

#3fa9ab · #413fab

#ab3f74 · #74ab3f

Split-complementary

Open in tool →

#ab413f · #a9ab3f

#ab3fa9 · #ab773f · #3fab41

Contrast

#3f74ab as textRatioAAAA largeAAAFix
Aaon white
4.89:1passpassfail
  • AAA: use #325a86 as the text (7.14:1)
Aaon black
4.3:1failpassfail
  • AA: use #4279b3 as the text (4.62:1)
  • AAA: use #6e9ac9 as the text (7.13:1)
  • AA: or shift the background to #f7f7f7 (4.56:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f74ab 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

#3f74ab reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f74ab
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 #3f74ab and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f74ab-9cabc4-df534e-1f202d-e9f1f1?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