Color

#66cb5d

#66cb5d
hex#66cb5d
rgbrgb(102, 203, 93)
hslhsl(115, 51%, 58%)
oklchoklch(0.757 0.176 142.1)
Closest name: Emerald Green (#50c878)Relative luminance 0.4633

Colors that go with #66cb5d

Charcoal, Blue and Royal Blue 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 →

#c15dcb

#9dcb5d · #5dcb8b

#5d66cb · #cb5d66

Split-complementary

Open in tool →

#8b5dcb · #cb5d9d

#5d9dcb · #c15dcb · #cb8b5d

Contrast

#66cb5d as textRatioAAAA largeAAAFix
Aaon white
2.05:1failfailfail
  • AA: use #33872c as the text (4.52:1)
  • AAA: use #266420 as the text (7.18:1)
  • AA: or shift the background to #474747 (4.54:1)
  • AAA: or shift the background to #292929 (7.11:1)
Aaon black
10.27:1passpasspassPasses 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 #66cb5d 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 #66cb5d
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 #66cb5d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/66cb5d-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