Color

#3f87ab

#3f87ab
hex#3f87ab
rgbrgb(63, 135, 171)
hslhsl(200, 46%, 46%)
oklchoklch(0.593 0.09 232.9)
Closest name: steelblue (#4682b4)Relative luminance 0.2132

Colors that go with #3f87ab

Charcoal, Copper and Royal Blue 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 #3f87ab

Tints & shades

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

Harmonies

Complementary

Open in tool →

#ab633f

#3fab99 · #3f51ab

#ab3f87 · #87ab3f

Split-complementary

Open in tool →

#ab3f51 · #ab993f

#993fab · #ab633f · #51ab3f

Contrast

#3f87ab as textRatioAAAA largeAAAFix
Aaon white
3.99:1failpassfail
  • AA: use #3a7c9c as the text (4.62:1)
  • AAA: use #2c5e77 as the text (7.06:1)
  • AA: or shift the background to #141414 (4.62:1)
Aaon black
5.26:1passpassfail
  • AAA: use #579ec1 as the text (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f87ab as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Palettes built around it

Fonts for this mood

#3f87ab reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f87ab
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 #3f87ab and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f87ab-9cb2c4-df4e64-1f232d-e9f1f0?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