Color

#5b15cb

#5b15cb
hex#5b15cb
rgbrgb(91, 21, 203)
hslhsl(263, 81%, 44%)
oklchoklch(0.444 0.239 289.3)
Closest name: Blurple (#5539cc)Relative luminance 0.0707

Colors that go with #5b15cb

Charcoal, Royal Blue and Cobalt 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 →

#85cb15

#152bcb · #b615cb

#cb5b15 · #15cb5b

Split-complementary

Open in tool →

#cbb615 · #2bcb15

#cb152b · #85cb15 · #15cbb6

Contrast

#5b15cb as textRatioAAAA largeAAAFix
Aaon white
8.7:1passpasspassPasses AAA — no fix needed.
Aaon black
2.41:1failfailfail
  • AA: use #8f54ed as the text (4.66:1)
  • AAA: use #ad82f2 as the text (7.25:1)
  • AA: or shift the background to #bdbdbd (4.63:1)
  • AAA: or shift the background to #e8e8e8 (7.1:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #5b15cb as the background.

Brands using this color

Fonts for this mood

#5b15cb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #5b15cb
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 #5b15cb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/5b15cb-b09cc4-dfd04e-2b1f2d-e9eaf1?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