# #21ca51

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

## Values

- Hex: `#21ca51`
- RGB: rgb(33, 202, 81)
- HSL: hsl(137, 72%, 46%)
- OKLCH: oklch(0.734 0.209 147.1)
- Relative luminance: 0.4316
- Nearest named color: Battletoad (#11cc55, Δ 0.572) — https://brandsweets.com/colors/battletoad
- Moods: vivid
- Page: https://brandsweets.com/colors/21ca51

## Tints & shades

- Tints (toward white): #28dc5b, #3ee06c, #58e480, #6ee791, #84eba1, #9aefb2, #b0f2c3, #caf6d7, #e0fae8, #f6fef8
- Shades (toward black): #1eb84a, #1ba743, #18913a, #157f33, #126e2c, #0f5c25, #0c4b1e, #093515, #06230e, #031207

## Harmonies

- Complementary: #ca219a
- Analogous: #45ca21, #21caa5
- Triadic: #5121ca, #ca5121
- Split-complementary: #a521ca, #ca2145
- Tetradic: #2145ca, #ca219a, #caa521

## Colors that go with #21ca51

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

- **Blue** #0000ff [pool] — 4 real palettes, including Minecraft's brand system and Spotify's brand system put Blue beside #21ca51, as the accent. Seen in: Minecraft (https://brandsweets.com/colors/brands/minecraft-net), Spotify (https://brandsweets.com/colors/brands/spotify), Unity (https://brandsweets.com/colors/brands/unity-com), MongoDB (https://brandsweets.com/colors/brands/mongodb-com). — https://brandsweets.com/colors/blue
- **Charcoal** #36454f [role, pool] — Charcoal is the body-text near-black for #21ca51: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. Seen in: Docker (https://brandsweets.com/colors/brands/docker-com), Mint Modern (https://brandsweets.com/palettes/modern#mint-modern), Zendesk (https://brandsweets.com/colors/brands/zendesk-com). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #21ca51 in 6 real palettes, including Brilliant's brand system and Docker's brand system, as the accent. Seen in: Brilliant (https://brandsweets.com/colors/brands/brilliant-org), Docker (https://brandsweets.com/colors/brands/docker-com), MongoDB (https://brandsweets.com/colors/brands/mongodb-com), Khan Academy (https://brandsweets.com/colors/brands/khanacademy-org). — https://brandsweets.com/colors/royalblue
- **Taupe** #483c32 [pool] — Taupe is paired with #21ca51 in 9 real palettes, including Obsidian's brand system and WhatsApp's brand system, as the text colour against it. Seen in: Obsidian (https://brandsweets.com/colors/brands/obsidian-md), WhatsApp (https://brandsweets.com/colors/brands/whatsapp-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net), Chime (https://brandsweets.com/colors/brands/chime-com). — https://brandsweets.com/colors/taupe
- **Violet** #ee82ee [harmony: complementary] — Violet sits directly opposite #21ca51 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
- **Hot Pink** #ff69b4 [harmony, pool: split] — Hot Pink is a split-complement of #21ca51: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Terminal (https://brandsweets.com/palettes/technical#terminal). — https://brandsweets.com/colors/hotpink
- **Cornflower Blue** #6495ed [harmony, pool: triadic] — Cornflower Blue completes a triad with #21ca51 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Terminal (https://brandsweets.com/palettes/technical#terminal), Spotify (https://brandsweets.com/colors/brands/spotify). — https://brandsweets.com/colors/cornflowerblue
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #21ca51 in 3 real palettes, including Playground and Learning App, as the lead colour. Seen in: Playground (https://brandsweets.com/palettes/bold#playground), Learning App (https://brandsweets.com/palettes/playful#learning-app), Citrus Grove (https://brandsweets.com/palettes/warm#citrus-grove). — https://brandsweets.com/colors/darkorange

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

- On white (#ffffff): 2.18:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #168836 (4.56:1); AA: background → #424242 (4.61:1); AAA: text → #106528 (7.21:1); AAA: background → #242424 (7.12:1)
- On black (#000000): 9.63:1 — AA pass, AA-large pass, AAA pass

## Brands using this color

- **Brilliant** — primary #2ccc54 (Δ 0.76) — https://brandsweets.com/colors/brands/brilliant-org

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/21ca51-a2bead-bb59d4-1f2d29-ebf1e9?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: "#21ca51" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.