Color

#3f5183

#3f5183
hex#3f5183
rgbrgb(63, 81, 131)
hslhsl(224, 35%, 38%)
oklchoklch(0.444 0.086 267.8)
Closest name: Assassin (#2d4f83)Relative luminance 0.0858

Colors that go with #3f5183

Sea Green, Steel Blue and 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 #3f5183

Tints & shades

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

Harmonies

Complementary

Open in tool →

#83713f

#3f7383 · #4f3f83

#833f51 · #51833f

Split-complementary

Open in tool →

#834f3f · #73833f

#833f73 · #83713f · #3f834f

Contrast

#3f5183 as textRatioAAAA largeAAAFix
Aaon white
7.73:1passpasspassPasses AAA — no fix needed.
Aaon black
2.72:1failfailfail
  • AA: use #5d74b1 as the text (4.6:1)
  • AAA: use #8797c5 as the text (7.26:1)
  • AA: or shift the background to #c7c7c7 (4.57:1)
  • AAA: or shift the background to #f5f5f5 (7.09:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f5183 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

#3f5183 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f5183
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 #3f5183 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f5183-9ca2c4-df724e-221f2d-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