Color

#3f598d

#3f598d
hex#3f598d
rgbrgb(63, 89, 141)
hslhsl(220, 38%, 40%)
oklchoklch(0.468 0.091 263.2)
Closest name: Dusk (#4e5481)Relative luminance 0.1012

Colors that go with #3f598d

Charcoal, Sea Green and Steel 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 #3f598d

Tints & shades

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

Harmonies

Complementary

Open in tool →

#8d733f

#3f808d · #4c3f8d

#8d3f59 · #598d3f

Split-complementary

Open in tool →

#8d4c3f · #808d3f

#8d3f80 · #8d733f · #3f8d4c

Contrast

#3f598d as textRatioAAAA largeAAAFix
Aaon white
6.94:1passpassfail
  • AAA: use #3e5789 as the text (7.17:1)
Aaon black
3.02:1failpassfail
  • AA: use #5675b3 as the text (4.59:1)
  • AAA: use #8098c6 as the text (7.22:1)
  • AA: or shift the background to #d1d1d1 (4.55:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f598d 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

#3f598d reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f598d
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 #3f598d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f598d-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