Color

#581b8d

#581b8d
hex#581b8d
rgbrgb(88, 27, 141)
hslhsl(272, 68%, 33%)
oklchoklch(0.385 0.173 303)
Closest name: Intergalactic Settlement (#5b1e8b)Relative luminance 0.0478

Colors that go with #581b8d

Crimson, Royal Blue and Olive Green 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 →

#508d1b

#1f1b8d · #8d1b8a

#8d581b · #1b8d58

Split-complementary

Open in tool →

#8a8d1b · #1b8d1f

#8d1f1b · #508d1b · #1b8a8d

Contrast

#581b8d as textRatioAAAA largeAAAFix
Aaon white
10.73:1passpasspassPasses AAA — no fix needed.
Aaon black
1.96:1failfailfail
  • AA: use #9b4fde as the text (4.57:1)
  • AAA: use #b67ee7 as the text (7.13:1)
  • AA: or shift the background to #a8a8a8 (4.51:1)
  • AAA: or shift the background to #d1d1d1 (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #581b8d 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

#581b8d reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #581b8d
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 #581b8d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/581b8d-b69cc4-c5cb62-2d1f2d-eae9f1?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