Color

#b4181e

#b4181e
hex#b4181e
rgbrgb(180, 24, 30)
hslhsl(358, 76%, 40%)
oklchoklch(0.494 0.188 26.4)
Closest name: firebrick (#b22222)Relative luminance 0.1045

Colors that go with #b4181e

Royal Blue, Teal and Amber 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 →

#18b4ae

#b4186b · #b46118

#1eb418 · #181eb4

Split-complementary

Open in tool →

#18b461 · #186bb4

#6bb418 · #18b4ae · #6118b4

Contrast

#b4181e as textRatioAAAA largeAAAFix
Aaon white
6.8:1passpassfail
  • AAA: use #af181d as the text (7.07:1)
Aaon black
3.09:1failpassfail
  • AA: use #e2282e as the text (4.58:1)
  • AAA: use #eb6f74 as the text (7.06:1)
  • AA: or shift the background to #d4d4d4 (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #b4181e as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#b4181e reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #b4181e
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 #b4181e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/b4181e-c49f9c-62cb95-2d251f-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