Color

#3f288a

#3f288a
hex#3f288a
rgbrgb(63, 40, 138)
hslhsl(254, 55%, 35%)
oklchoklch(0.369 0.153 287.1)
Closest name: Galactic Civilization (#442288)Relative luminance 0.0441

Colors that go with #3f288a

Charcoal, Denim 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#738a28

#28428a · #70288a

#8a3f28 · #288a3f

Split-complementary

Open in tool →

#8a7028 · #428a28

#8a2842 · #738a28 · #288a70

Contrast

#3f288a as textRatioAAAA largeAAAFix
Aaon white
11.16:1passpasspassPasses AAA — no fix needed.
Aaon black
1.88:1failfailfail
  • AA: use #7e65d2 as the text (4.68:1)
  • AAA: use #9f8cde as the text (7.28:1)
  • AA: or shift the background to #a6a6a6 (4.58:1)
  • AAA: or shift the background to #cfcfcf (7.16:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f288a 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

#3f288a reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f288a
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 #3f288a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f288a-aa9cc4-dfbb4e-291f2d-e9ebf1?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