Color

#51fa42

#51fa42
hex#51fa42
rgbrgb(81, 250, 66)
hslhsl(115, 95%, 62%)
oklchoklch(0.865 0.259 141.9)
Closest name: Cathode Green (#00ff55)Relative luminance 0.7051

Colors that go with #51fa42

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 →

#eb42fa

#adfa42 · #42fa8f

#4251fa · #fa4251

Split-complementary

Open in tool →

#8f42fa · #fa42ad

#42adfa · #eb42fa · #fa8f42

Contrast

#51fa42 as textRatioAAAA largeAAAFix
Aaon white
1.39:1failfailfail
  • AA: use #0e8603 as the text (4.74:1)
  • AAA: use #0b6803 as the text (7.01:1)
  • AA: or shift the background to #5e5e5e (4.66:1)
  • AAA: or shift the background to #424242 (7.23:1)
Aaon black
15.1:1passpasspassPasses 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 #51fa42 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 #51fa42
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 #51fa42 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/51fa42-a2bea3-8d4edf-1f2d24-eef1e9?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