Color

#21f241

#21f241
hex#21f241
rgbrgb(33, 242, 65)
hslhsl(129, 89%, 54%)
oklchoklch(0.837 0.262 144.2)
Closest name: Becquerel (#4bec13)Relative luminance 0.6421

Colors that go with #21f241

Violet, Deep Sky Blue and Hot Pink 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 →

#f221d3

#6af221 · #21f2a9

#4121f2 · #f24121

Split-complementary

Open in tool →

#a921f2 · #f2216a

#216af2 · #f221d3 · #f2a921

Contrast

#21f241 as textRatioAAAA largeAAAFix
Aaon white
1.52:1failfailfail
  • AA: use #08871b as the text (4.68:1)
  • AAA: use #066514 as the text (7.29:1)
  • AA: or shift the background to #595959 (4.62:1)
  • AAA: or shift the background to #3d3d3d (7.16:1)
Aaon black
13.84:1passpasspassPasses AAA — no fix needed.

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #21f241 as the background.

Brands using this color

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

mcpConnect your agent — build around #21f241
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 #21f241 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/21f241-a2bea9-ae4edf-1f2d27-ecf1e9?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