Color

#511d9a

#511d9a
hex#511d9a
rgbrgb(81, 29, 154)
hslhsl(265, 68%, 36%)
oklchoklch(0.39 0.184 295.1)
Closest name: Intergalactic Settlement (#5b1e8b)Relative luminance 0.0496

Colors that go with #511d9a

Royal Blue, Cobalt 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 →

#669a1d

#1d289a · #901d9a

#9a511d · #1d9a51

Split-complementary

Open in tool →

#9a901d · #289a1d

#9a1d28 · #669a1d · #1d9a90

Contrast

#511d9a as textRatioAAAA largeAAAFix
Aaon white
10.54:1passpasspassPasses AAA — no fix needed.
Aaon black
1.99:1failfailfail
  • AA: use #9058df as the text (4.65:1)
  • AAA: use #ad83e7 as the text (7.18:1)
  • AA: or shift the background to #ababab (4.59:1)
  • AAA: or shift the background to #d4d4d4 (7.11:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #511d9a as the background.

Brands using this color

Fonts for this mood

#511d9a reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #511d9a
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 #511d9a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/511d9a-b19cc4-dfd54e-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