Color

#515f70

#515f70
hex#515f70
rgbrgb(81, 95, 112)
hslhsl(213, 16%, 38%)
oklchoklch(0.48 0.033 253.4)
Closest name: Concrete Landscape (#5c606e)Relative luminance 0.111

Colors that go with #515f70

Sienna, Cadet Blue and Champagne 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 →

#706251

#516f70 · #535170

#70515f · #5f7051

Split-complementary

Open in tool →

#705351 · #6f7051

#70516f · #706251 · #517053

Contrast

#515f70 as textRatioAAAA largeAAAFix
Aaon white
6.52:1passpassfail
  • AAA: use #4d5a6a as the text (7.03:1)
Aaon black
3.22:1failpassfail
  • AA: use #65768b as the text (4.52:1)
  • AAA: use #8997a9 as the text (7.06:1)
  • AA: or shift the background to #d9d9d9 (4.62:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #515f70 as the background.

Brands using this color

mcpConnect your agent — build around #515f70
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 #515f70 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/515f70-9ca9c4-df584e-1f202d-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