Color

#515d70

#515d70
hex#515d70
rgbrgb(81, 93, 112)
hslhsl(217, 16%, 38%)
oklchoklch(0.475 0.034 259.5)
Closest name: Concrete Landscape (#5c606e)Relative luminance 0.1075

Colors that go with #515d70

Sienna, Blue and Cadet 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 →

#706551

#516d70 · #555170

#70515d · #5d7051

Split-complementary

Open in tool →

#705551 · #6d7051

#70516d · #706551 · #517055

Contrast

#515d70 as textRatioAAAA largeAAAFix
Aaon white
6.67:1passpassfail
  • AAA: use #4d586a as the text (7.19:1)
Aaon black
3.15:1failpassfail
  • AA: use #67768e as the text (4.56:1)
  • AAA: use #8c98ab as the text (7.19:1)
  • AA: or shift the background to #d6d6d6 (4.59:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #515d70 as the background.

Brands using this color

mcpConnect your agent — build around #515d70
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 #515d70 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/515d70-9ca7c4-df624e-201f2d-e9f0f1?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