Playground
Open in tool →Orange, blue and green — the colors of playground equipment; loud, cheerful, obviously for kids.
Color
#18c357
#18c357
hex
#18c357rgb
rgb(24, 195, 87)hsl
hsl(142, 78%, 43%)oklch
oklch(0.715 0.197 148.9)Closest name: Intoxicate (#11bb55)Relative luminance 0.3991
Colors that go with #18c357
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.
Charcoal #36454f
neutralshippedCharcoal is the body-text near-black for #18c357: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Blue #0000ff
shipped4 real palettes, including Spotify's brand system and Minecraft's brand system put Blue beside #18c357, as the accent.
Royal Blue #4169e1
shippedRoyal Blue is paired with #18c357 in 6 real palettes, including Brilliant's brand system and Docker's brand system, as the accent.
Taupe #483c32
shippedTaupe is paired with #18c357 in 9 real palettes, including Obsidian's brand system and Chime's brand system, as the text colour against it.
Fuchsia #ff00ff
complementaryFuchsia sits directly opposite #18c357 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-complementshippedHot Pink is a split-complement of #18c357: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Cornflower Blue #6495ed
triadicshippedCornflower Blue completes a triad with #18c357 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Dark Olive Green #556b2f
shippedDark Olive Green shows up next to #18c357 in 3 real palettes, including Undergrowth and 7-Eleven's brand system, as the supporting colour.
Real palettes that use #18c357
Tints & shades
Harmonies
Contrast
| #18c357 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.34:1 | fail | fail | fail | |
Aaon black | 8.98:1 | 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 #18c357 as the background.
Brands using this color
Palettes built around it
mcpConnect your agent — build around #18c357
live endpointPoint 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.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #18c357 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/18c357-a2beaf-c659d4-1f2d2a-eaf1e9?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