# #21b040

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

## Values

- Hex: `#21b040`
- RGB: rgb(33, 176, 64)
- HSL: hsl(133, 68%, 41%)
- OKLCH: oklch(0.663 0.192 145.9)
- Relative luminance: 0.3174
- Nearest named color: Fennel Fiasco (#00aa44, Δ 2.107) — https://brandsweets.com/colors/fennel-fiasco
- Moods: vivid
- Page: https://brandsweets.com/colors/21b040

## Tints & shades

- Tints (toward white): #26c94a, #31d855, #4bdd6b, #65e280, #7ee795, #94eba7, #aeefbc, #c7f4d1, #ddf8e3, #f6fdf8
- Shades (toward black): #1e9f3a, #1c9235, #18812f, #156f29, #136324, #10511e, #0c4018, #092f11, #07220d, #031106

## Harmonies

- Complementary: #b02191
- Analogous: #4ab021, #21b087
- Triadic: #4021b0, #b04021
- Split-complementary: #8721b0, #b0214a
- Tetradic: #214ab0, #b02191, #b08721

## Colors that go with #21b040

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 Spotify's brand system and Minecraft's brand system put Blue beside #21b040, as the accent. Seen in: Spotify (https://brandsweets.com/colors/brands/spotify), Minecraft (https://brandsweets.com/colors/brands/minecraft-net), Unity (https://brandsweets.com/colors/brands/unity-com), Instacart (https://brandsweets.com/colors/brands/instacart-com). — https://brandsweets.com/colors/blue
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #21b040 in 4 real palettes, including Console Light and Telehealth, as the lead colour. Seen in: Console Light (https://brandsweets.com/palettes/technical#console-light), Telehealth (https://brandsweets.com/palettes/modern#telehealth), Brilliant (https://brandsweets.com/colors/brands/brilliant-org), Khan Academy (https://brandsweets.com/colors/brands/khanacademy-org). — https://brandsweets.com/colors/royalblue
- **Taupe** #483c32 [pool] — Taupe is paired with #21b040 in 9 real palettes, including Obsidian's brand system and Meadow, as the text colour against it. Seen in: Obsidian (https://brandsweets.com/colors/brands/obsidian-md), Meadow (https://brandsweets.com/palettes/light#meadow), Chime (https://brandsweets.com/colors/brands/chime-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net). — https://brandsweets.com/colors/taupe
- **Fuchsia** #ff00ff [harmony: complementary] — Fuchsia sits directly opposite #21b040 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/fuchsia
- **Medium Purple** #9370db [harmony, pool: split] — Medium Purple is a split-complement of #21b040: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Obsidian (https://brandsweets.com/colors/brands/obsidian-md), Next.js (https://brandsweets.com/colors/brands/nextjs-org). — https://brandsweets.com/colors/mediumpurple
- **Charcoal** #36454f [role, pool] — Charcoal is the body-text near-black for #21b040: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. Seen in: Zendesk (https://brandsweets.com/colors/brands/zendesk-com), Mint Modern (https://brandsweets.com/palettes/modern#mint-modern). — https://brandsweets.com/colors/charcoal
- **Cornflower Blue** #6495ed [harmony, pool: triadic] — Cornflower Blue completes a triad with #21b040 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Spotify (https://brandsweets.com/colors/brands/spotify), Terminal (https://brandsweets.com/palettes/technical#terminal). — https://brandsweets.com/colors/cornflowerblue
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #21b040 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): 2.86:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #198531 (4.73:1); AA: background → #303030 (4.62:1); AAA: text → #146726 (7.01:1); AAA: background → #080808 (7.01:1)
- On black (#000000): 7.35:1 — AA pass, AA-large pass, AAA pass

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/21b040-a2beab-b84edf-1f2d28-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: "#21b040" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.