Color
#21cb0b
#21cb0brgb(33, 203, 11)hsl(113, 90%, 42%)oklch(0.732 0.243 141.9)Colors that go with #21cb0b
Taupe, 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.
Taupe #483c32
shippedTaupe is paired with #21cb0b in 8 real palettes, including Obsidian's brand system and WhatsApp's brand system, as the text colour against it.
Violet #ee82ee
complementaryViolet sits directly opposite #21cb0b 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 #21cb0b: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Blue #0000ff
shipped3 real palettes, including Minecraft's brand system and Spotify's brand system put Blue beside #21cb0b, as the accent.
Cornflower Blue #6495ed
triadicshippedCornflower Blue completes a triad with #21cb0b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Dark Orange #ff8c00
shippedDark Orange shows up next to #21cb0b in 3 real palettes, including Learning App and Playground, as the accent.
Light Coral #f08080
triadicshippedLight Coral completes a triad with #21cb0b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Charcoal #36454f
neutralCharcoal is the body-text near-black for #21cb0b: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Real palettes that use #21cb0b
Tints & shades
Harmonies
Contrast
| #21cb0b as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.18:1 | fail | fail | fail | |
Aaon black | 9.61:1 | 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 #21cb0b 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 #21cb0b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/21cb0b-a2bea2-884edf-1f2d24-eef1e9?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