Color
#66c299
#66c299rgb(102, 194, 153)hsl(153, 43%, 58%)oklch(0.746 0.108 163)Colors that go with #66c299
Charcoal, Plum and 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.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #66c299: softer than #000 and cool enough to feel like part of the same palette.
Plum #dda0dd
complementaryshippedPlum sits directly opposite #66c299 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Blue #0000ff
shipped4 real palettes, including Unity's brand system and Spotify's brand system put Blue beside #66c299, as the supporting colour.
Dark Olive Green #556b2f
shippedDark Olive Green shows up next to #66c299 in 4 real palettes, including Undergrowth and Forest Floor, as the supporting colour.
Hunter Green #355e3b
shippedHunter Green is paired with #66c299 in 4 real palettes, including Neon's brand system and Pine & Birch, as the supporting colour.
Mustard Yellow #ffdb58
shipped4 real palettes, including Fresh Juice and Crayon Box put Mustard Yellow beside #66c299, as the supporting colour.
Slate Gray #708090
shipped7 real palettes, including Ledger Dark and Indigo SaaS put Slate Gray beside #66c299, as the supporting colour.
Taupe #483c32
shippedTaupe is paired with #66c299 in 26 real palettes, including Resort and Undergrowth, as the text colour against it.
Real palettes that use #66c299
Tints & shades
Harmonies
Contrast
| #66c299 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.16:1 | fail | fail | fail | |
Aaon black | 9.74:1 | pass | pass | pass | Passes 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 #66c299 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
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.
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
›analyze #66c299 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/66c299-a2beb5-d459cc-1f2d2d-e9f1ea?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md