Color

#515d90

#515d90
hex#515d90
rgbrgb(81, 93, 144)
hslhsl(229, 28%, 44%)
oklchoklch(0.491 0.083 272.9)
Closest name: Dusk (#4e5481)Relative luminance 0.1159

Colors that go with #515d90

Charcoal, Sea Green and Dark 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.

Real palettes that use #515d90

Tints & shades

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

Harmonies

Complementary

Open in tool →

#908451

#517c90 · #655190

#90515c · #5c9051

Split-complementary

Open in tool →

#906551 · #7c9051

#90517c · #908451 · #519065

Contrast

#515d90 as textRatioAAAA largeAAAFix
Aaon white
6.33:1passpassfail
  • AAA: use #4b5686 as the text (7.06:1)
Aaon black
3.32:1failpassfail
  • AA: use #6672a9 as the text (4.54:1)
  • AAA: use #8d96bf as the text (7.25:1)
  • AA: or shift the background to #dbdbdb (4.57:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #515d90 as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Palettes built around it

mcpConnect your agent — build around #515d90
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 #515d90 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/515d90-9c9fc4-df7e4e-231f2d-e9eef1?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