Color
#66ef39
#66ef39rgb(102, 239, 57)hsl(105, 85%, 58%)oklch(0.843 0.244 139.4)Colors that go with #66ef39
Deep Sky Blue, Violet 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.
Deep Sky Blue #00bfff
triadicshippedDeep Sky Blue completes a triad with #66ef39 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Violet #ee82ee
complementaryViolet sits directly opposite #66ef39 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Hot Pink #ff69b4
split-complementHot Pink is a split-complement of #66ef39: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Blue #0000ff
shippedTwo real palettes: MongoDB's brand system and Robinhood's brand system put Blue beside #66ef39, as the accent.
Charcoal #36454f
neutralCharcoal is the body-text near-black for #66ef39: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Lilac #c8a2c8
split-complementLilac is a split-complement of #66ef39: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Lime Green #32cd32
shippedTwo real palettes: Monster Energy's brand system and Duolingo's brand system put Lime Green beside #66ef39, as the accent.
Red #ff0000
shippedRed is paired with #66ef39 in two real palettes: Gatorade's brand system and Wise's brand system, as the supporting colour.
Real palettes that use #66ef39
Tints & shades
Harmonies
Contrast
| #66ef39 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 1.5:1 | fail | fail | fail | |
Aaon black | 13.97:1 | 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 #66ef39 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 #66ef39 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/66ef39-a6bea2-754edf-1f2d22-eff1e9?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