Color

#b20101

#b20101
hex#b20101
rgbrgb(178, 1, 1)
hslhsl(0, 99%, 35%)
oklchoklch(0.48 0.196 29.2)
Closest name: All Systems Red (#b30103)Relative luminance 0.0949

Tints & shades

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

Harmonies

Complementary

Open in tool →

#01b2b2

#b20159 · #b25901

#01b201 · #0101b2

Split-complementary

Open in tool →

#01b259 · #0159b2

#59b201 · #01b2b2 · #5901b2

Contrast

#b20101 as textRatioAAAA largeAAAFix
Aaon white
7.25:1passpasspassPasses AAA — no fix needed.
Aaon black
2.9:1failfailfail
  • AA: use #ef0101 as the text (4.67:1)
  • AAA: use #fe6262 as the text (7.14:1)
  • AA: or shift the background to #cccccc (4.51:1)
  • AAA: or shift the background to #fcfcfc (7.06:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #b20101 as the background.

Brands using this color

Fonts for this mood

#b20101 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #b20101
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 #b20101 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/b20101-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