Color

#d21436

#d21436
hex#d21436
rgbrgb(210, 20, 54)
hslhsl(349, 83%, 45%)
oklchoklch(0.552 0.214 21)
Closest name: crimson (#dc143c)Relative luminance 0.1447

Colors that go with #d21436

Charcoal, Royal Blue and Sea Green 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 →

#14d2af

#d21496 · #d25014

#36d214 · #1436d2

Split-complementary

Open in tool →

#14d250 · #1496d2

#96d214 · #14d2af · #5014d2

Contrast

#d21436 as textRatioAAAA largeAAAFix
Aaon white
5.39:1passpassfail
  • AAA: use #b1102e as the text (7.04:1)
Aaon black
3.89:1failpassfail
  • AA: use #e5153b as the text (4.5:1)
  • AAA: use #f16a83 as the text (7.13:1)
  • AA: or shift the background to #ebebeb (4.52:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #d21436 as the background.

Brands using this color

Fonts for this mood

#d21436 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #d21436
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 #d21436 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/d21436-c49c9f-62cb85-2d231f-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