Color

#391c78

#391c78
hex#391c78
rgbrgb(57, 28, 120)
hslhsl(259, 62%, 29%)
oklchoklch(0.329 0.145 290.5)
Closest name: Explorer of the Galaxies (#3a1f76)Relative luminance 0.0306

Colors that go with #391c78

Charcoal, Royal Blue and Crimson 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 →

#5b781c

#1c2d78 · #671c78

#78391c · #1c7839

Split-complementary

Open in tool →

#78671c · #2d781c

#781c2d · #5b781c · #1c7867

Contrast

#391c78 as textRatioAAAA largeAAAFix
Aaon white
13.03:1passpasspassPasses AAA — no fix needed.
Aaon black
1.61:1failfailfail
  • AA: use #855ed9 as the text (4.6:1)
  • AAA: use #a487e3 as the text (7.15:1)
  • AA: or shift the background to #999999 (4.57:1)
  • AAA: or shift the background to #bfbfbf (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 #391c78 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

#391c78 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #391c78
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 #391c78 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/391c78-ad9cc4-dfc74e-2a1f2d-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