Color

#3f575f

#3f575f
hex#3f575f
rgbrgb(63, 87, 95)
hslhsl(195, 20%, 31%)
oklchoklch(0.44 0.032 220.4)
Closest name: All Nighter (#455454)Relative luminance 0.087

Colors that go with #3f575f

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.

Real palettes that use #3f575f

Tints & shades

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

Harmonies

Complementary

Open in tool →

#5f473f

#3f5f57 · #3f475f

#5f3f57 · #575f3f

Split-complementary

Open in tool →

#5f3f47 · #5f573f

#573f5f · #5f473f · #475f3f

Contrast

#3f575f as textRatioAAAA largeAAAFix
Aaon white
7.66:1passpasspassPasses AAA — no fix needed.
Aaon black
2.74:1failfailfail
  • AA: use #5a7b87 as the text (4.62:1)
  • AAA: use #7b9ca7 as the text (7.16:1)
  • AA: or shift the background to #c7c7c7 (4.53:1)
  • AAA: or shift the background to #f5f5f5 (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 #3f575f 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 #3f575f
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 #3f575f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f575f-9cb5c4-df4e70-1f242d-e9f1ef?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