Color

#66e178

#66e178
hex#66e178
rgbrgb(102, 225, 120)
hslhsl(129, 67%, 64%)
oklchoklch(0.815 0.182 146.6)
Closest name: Grotesque Green (#64e986)Relative luminance 0.5803

Colors that go with #66e178

Deep Sky Blue, Taupe and Violet 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 →

#e166ce

#91e166 · #66e1b6

#7866e1 · #e17866

Split-complementary

Open in tool →

#b666e1 · #e16691

#6691e1 · #e166ce · #e1b666

Contrast

#66e178 as textRatioAAAA largeAAAFix
Aaon white
1.67:1failfailfail
  • AA: use #1b882b as the text (4.56:1)
  • AAA: use #146620 as the text (7.12:1)
  • AA: or shift the background to #545454 (4.55:1)
  • AAA: or shift the background to #383838 (7.04:1)
Aaon black
12.61:1passpasspassPasses 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 #66e178 as the background.

Brands using this color

mcpConnect your agent — build around #66e178
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 #66e178 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/66e178-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