Color

#d21931

#d21931
hex#d21931
rgbrgb(210, 25, 49)
hslhsl(352, 79%, 46%)
oklchoklch(0.553 0.212 22.9)
Closest name: Angry Tomato (#d82029)Relative luminance 0.1462

Colors that go with #d21931

Charcoal, Royal Blue and Steel 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#19d2b9

#d2198e · #d25d19

#31d219 · #1931d2

Split-complementary

Open in tool →

#19d25d · #198ed2

#8ed219 · #19d2b9 · #5d19d2

Contrast

#d21931 as textRatioAAAA largeAAAFix
Aaon white
5.35:1passpassfail
  • AAA: use #ad1429 as the text (7.22:1)
Aaon black
3.92:1failpassfail
  • AA: use #e41b36 as the text (4.51:1)
  • AAA: use #ee6d7e as the text (7.12:1)
  • AA: or shift the background to #ededed (4.57:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #d21931 as the background.

Brands using this color

Fonts for this mood

#d21931 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #d21931
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 #d21931 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/d21931-c49c9d-62cb8a-2d231f-f1e9ee?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