# #21fb09

A color — vivid. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#21fb09`
- RGB: rgb(33, 251, 9)
- HSL: hsl(114, 97%, 51%)
- OKLCH: oklch(0.858 0.288 142.1)
- Relative luminance: 0.6934
- Nearest named color: Acid (#00ff22, Δ 1.035) — https://brandsweets.com/colors/acid
- Moods: vivid
- Page: https://brandsweets.com/colors/21fb09

## Tints & shades

- Tints (toward white): #38fc22, #4afc36, #60fc4f, #77fd68, #8efd81, #a0fd96, #b7feaf, #cdfec8, #dffedc, #f6fff5
- Shades (toward black): #1ae704, #18d303, #15ba03, #12a102, #108d02, #0d7402, #0a5a01, #074101, #052d01, #021400

## Harmonies

- Complementary: #e309fb
- Analogous: #9afb09, #09fb6a
- Triadic: #0921fb, #fb0921
- Split-complementary: #6a09fb, #fb099a
- Tetradic: #099afb, #e309fb, #fb6a09

## Colors that go with #21fb09

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Violet** #ee82ee [harmony: complementary] — Violet sits directly opposite #21fb09 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/violet
- **Deep Sky Blue** #00bfff [harmony, pool: triadic] — Deep Sky Blue completes a triad with #21fb09 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Remix (https://brandsweets.com/colors/brands/remix-run). — https://brandsweets.com/colors/deepskyblue
- **Hot Pink** #ff69b4 [harmony: split] — Hot Pink is a split-complement of #21fb09: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. — https://brandsweets.com/colors/hotpink
- **Charcoal** #36454f [role] — Charcoal is the body-text near-black for #21fb09: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. — https://brandsweets.com/colors/charcoal
- **Plum** #dda0dd [harmony: split] — Plum is a split-complement of #21fb09: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. — https://brandsweets.com/colors/plum
- **Light Coral** #f08080 [harmony: triadic] — Light Coral completes a triad with #21fb09 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. — https://brandsweets.com/colors/lightcoral
- **Medium Aquamarine** #66cdaa [harmony: analogous] — Medium Aquamarine is #21fb09's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. — https://brandsweets.com/colors/mediumaquamarine
- **Blue** #0000ff [pool] — MongoDB's brand system puts Blue beside #21fb09, as the accent. Seen in: MongoDB (https://brandsweets.com/colors/brands/mongodb-com). — https://brandsweets.com/colors/blue

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 1.41:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #0f8802 (4.62:1); AA: background → #5e5e5e (4.59:1); AAA: text → #0b6402 (7.4:1); AAA: background → #424242 (7.11:1)
- On black (#000000): 14.87:1 — AA pass, AA-large pass, AAA pass

## Curated palettes containing it

- **Laser** (neon, vivid, dark, technical) — #39ff14, #bf00ff, #00e5ff, #07070d, #eefaf0 — Laser green, violet and cyan — the synthwave/gaming set; keep the type near-white and let one neon own each screen. — tool: https://brandsweets.com/palettes/new/39ff14-bf00ff-00e5ff-07070d-eefaf0 — collection: https://brandsweets.com/palettes/neon

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/21fb09-a2bea2-8a4edf-1f2d24-eef1e9?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#21fb09" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.