Color

#3b505e

#3b505e
hex#3b505e
rgbrgb(59, 80, 94)
hslhsl(204, 23%, 30%)
oklchoklch(0.42 0.035 237.9)
Closest name: Abyssal (#404c57)Relative luminance 0.0748

Colors that go with #3b505e

Steel Blue, Teal and Sienna 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 →

#5e493b

#3b5e5b · #3b3e5e

#5e3b50 · #505e3b

Split-complementary

Open in tool →

#5e3b3e · #5e5b3b

#5b3b5e · #5e493b · #3e5e3b

Contrast

#3b505e as textRatioAAAA largeAAAFix
Aaon white
8.42:1passpasspassPasses AAA — no fix needed.
Aaon black
2.5:1failfailfail
  • AA: use #5a7b90 as the text (4.67:1)
  • AAA: use #7b99ad as the text (7:1)
  • AA: or shift the background to #bfbfbf (4.58:1)
  • AAA: or shift the background to #ebebeb (7.06:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3b505e as the background.

Brands using this color

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

Fonts for this mood

#3b505e reads as cool, muted, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3b505e
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 #3b505e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3b505e-9cafc4-df4e5a-1f222d-e9f1f0?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