Color

#d30909

#d30909
hex#d30909
rgbrgb(211, 9, 9)
hslhsl(0, 92%, 43%)
oklchoklch(0.547 0.221 28.9)
Closest name: Angry Tomato (#d82029)Relative luminance 0.1406

Colors that go with #d30909

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 →

#09d3d3

#d3096e · #d36e09

#09d309 · #0909d3

Split-complementary

Open in tool →

#09d36e · #096ed3

#6ed309 · #09d3d3 · #6e09d3

Contrast

#d30909 as textRatioAAAA largeAAAFix
Aaon white
5.51:1passpassfail
  • AAA: use #b00707 as the text (7.29:1)
Aaon black
3.81:1failpassfail
  • AA: use #eb0a0a as the text (4.58:1)
  • AAA: use #f96767 as the text (7.16:1)
  • AA: or shift the background to #ebebeb (4.62:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #d30909 as the background.

Brands using this color

Fonts for this mood

#d30909 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #d30909
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 #d30909 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/d30909-c4a19c-62cb98-2d251f-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