Color

#515c67

#515c67
hex#515c67
rgbrgb(81, 92, 103)
hslhsl(210, 12%, 36%)
oklchoklch(0.469 0.023 248.3)
Closest name: Blackwater (#545663)Relative luminance 0.1038

Colors that go with #515c67

Cadet Blue, Champagne and Copper 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 →

#675c51

#516767 · #515167

#67515c · #5c6751

Split-complementary

Open in tool →

#675151 · #676751

#675167 · #675c51 · #516751

Contrast

#515c67 as textRatioAAAA largeAAAFix
Aaon white
6.83:1passpassfail
  • AAA: use #4f5964 as the text (7.13:1)
Aaon black
3.08:1failpassfail
  • AA: use #697886 as the text (4.63:1)
  • AAA: use #8d99a5 as the text (7.23:1)
  • AA: or shift the background to #d4d4d4 (4.6:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #515c67 as the background.

Brands using this color

mcpConnect your agent — build around #515c67
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 #515c67 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/515c67-9cabc4-df514e-1f202d-e9f1f1?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