Color

#f51000

#f51000
hex#f51000
rgbrgb(245, 16, 0)
hslhsl(4, 100%, 48%)
oklchoklch(0.612 0.247 29.8)
Closest name: Assassin’s Red (#f60206)Relative luminance 0.1978

Tints & shades

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

Harmonies

Complementary

Open in tool →

#00e4f5

#f5006a · #f58b00

#00f510 · #1000f5

Split-complementary

Open in tool →

#00f58b · #006af5

#6af500 · #00e4f5 · #8b00f5

Contrast

#f51000 as textRatioAAAA largeAAAFix
Aaon white
4.24:1failpassfail
  • AA: use #eb1000 as the text (4.56:1)
  • AAA: use #b30c00 as the text (7.07:1)
  • AA: or shift the background to #0f0f0f (4.52:1)
Aaon black
4.96:1passpassfail
  • AAA: use #ff6257 as the text (7.14:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #f51000 as the background.

Brands using this color

Fonts for this mood

#f51000 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #f51000
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 #f51000 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/f51000-c4a39c-62cb9f-2d261f-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