Color

#ef3a2a

#ef3a2a
hex#ef3a2a
rgbrgb(239, 58, 42)
hslhsl(5, 86%, 55%)
oklchoklch(0.625 0.219 29.7)
Closest name: Arcade Fire (#ee3311)Relative luminance 0.2154

Colors that go with #ef3a2a

Charcoal, Steel Blue and Cadet 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 →

#2adeef

#ef2a7c · #ef9d2a

#2aef3a · #3a2aef

Split-complementary

Open in tool →

#2aef9d · #2a7cef

#7cef2a · #2adeef · #9d2aef

Contrast

#ef3a2a as textRatioAAAA largeAAAFix
Aaon white
3.96:1failpassfail
  • AA: use #e42311 as the text (4.62:1)
  • AAA: use #af1b0d as the text (7.03:1)
  • AA: or shift the background to #171717 (4.53:1)
Aaon black
5.31:1passpassfail
  • AAA: use #f36a5e as the text (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #ef3a2a as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#ef3a2a reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #ef3a2a
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 #ef3a2a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/ef3a2a-c4a49c-62cba1-2d261f-f1e9ec?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