Color

#3f3d99

#3f3d99
hex#3f3d99
rgbrgb(63, 61, 153)
hslhsl(241, 43%, 42%)
oklchoklch(0.418 0.146 279)
Closest name: Blueberry (#464196)Relative luminance 0.0669

Colors that go with #3f3d99

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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#98993d

#3d6a99 · #6d3d99

#993f3d · #3d993f

Split-complementary

Open in tool →

#996d3d · #6a993d

#993d6a · #98993d · #3d996d

Contrast

#3f3d99 as textRatioAAAA largeAAAFix
Aaon white
8.98:1passpasspassPasses AAA — no fix needed.
Aaon black
2.34:1failfailfail
  • AA: use #6f6dc5 as the text (4.67:1)
  • AAA: use #9392d3 as the text (7.29:1)
  • AA: or shift the background to #b8b8b8 (4.53:1)
  • AAA: or shift the background to #e6e6e6 (7.19:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f3d99 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

#3f3d99 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f3d99
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 #3f3d99 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f3d99-a19cc4-df9b4e-261f2d-e9edf1?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