Color

#b91b18

#b91b18
hex#b91b18
rgbrgb(185, 27, 24)
hslhsl(1, 77%, 41%)
oklchoklch(0.505 0.191 28.2)
Closest name: Bloodshed (#ba271a)Relative luminance 0.1116

Colors that go with #b91b18

Royal Blue, Steel Blue and Teal 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 →

#18b6b9

#b91866 · #b96b18

#18b91b · #1b18b9

Split-complementary

Open in tool →

#18b96b · #1866b9

#66b918 · #18b6b9 · #6b18b9

Contrast

#b91b18 as textRatioAAAA largeAAAFix
Aaon white
6.5:1passpassfail
  • AAA: use #b01917 as the text (7.01:1)
Aaon black
3.23:1failpassfail
  • AA: use #e22522 as the text (4.52:1)
  • AAA: use #ec716f as the text (7.16:1)
  • AA: or shift the background to #d9d9d9 (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 #b91b18 as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#b91b18 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #b91b18
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 #b91b18 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/b91b18-c4a19c-62cb9a-2d261f-f1e9ed?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