Color

#ff311f

#ff311f
hex#ff311f
rgbrgb(255, 49, 31)
hslhsl(5, 100%, 56%)
oklchoklch(0.646 0.24 29.9)
Closest name: red (#ff0000)Relative luminance 0.2356

Tints & shades

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

Harmonies

Complementary

Open in tool →

#1fecff

#ff1f7c · #ffa21f

#1fff31 · #311fff

Split-complementary

Open in tool →

#1fffa2 · #1f7cff

#7cff1f · #1fecff · #a11fff

Contrast

#ff311f as textRatioAAAA largeAAAFix
Aaon white
3.68:1failpassfail
  • AA: use #eb1400 as the text (4.53:1)
  • AAA: use #b30f00 as the text (7.04:1)
  • AA: or shift the background to #1c1c1c (4.63:1)
Aaon black
5.71:1passpassfail
  • AAA: use #ff6052 as the text (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #ff311f as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#ff311f reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #ff311f
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #ff311f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/ff311f-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