# #21c4bc

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

## Values

- Hex: `#21c4bc`
- RGB: rgb(33, 196, 188)
- HSL: hsl(177, 71%, 45%)
- OKLCH: oklch(0.742 0.123 189.5)
- Relative luminance: 0.4343
- Nearest named color: Emerald Bliss (#4cbdac, Δ 2.719) — https://brandsweets.com/colors/emerald-bliss
- Moods: vivid
- Page: https://brandsweets.com/colors/21c4bc

## Tints & shades

- Tints (toward white): #25dad1, #3fded6, #55e2db, #6be6e0, #85eae5, #9beeea, #b1f2ee, #c6f5f3, #e0faf9, #f6fefd
- Shades (toward black): #1eb3ab, #1ba19b, #18908a, #157e79, #126d68, #0f5754, #0c4643, #093432, #062321, #031111

## Harmonies

- Complementary: #c42129
- Analogous: #21c46b, #217bc4
- Triadic: #bc21c4, #c4bc21
- Split-complementary: #c4217b, #c46b21
- Tetradic: #6b21c4, #c42129, #7bc421

## Colors that go with #21c4bc

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

- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #21c4bc: softer than #000 and cool enough to feel like part of the same palette. Seen in: Lagoon (https://brandsweets.com/palettes/vivid#lagoon), N26 (https://brandsweets.com/colors/brands/n26-com), Docker (https://brandsweets.com/colors/brands/docker-com), Mint Modern (https://brandsweets.com/palettes/modern#mint-modern). — https://brandsweets.com/colors/charcoal
- **Blue** #0000ff [pool] — 4 real palettes, including Canva's brand system and Unity's brand system put Blue beside #21c4bc, as the accent. Seen in: Canva (https://brandsweets.com/colors/brands/canva-com), Unity (https://brandsweets.com/colors/brands/unity-com), Warp (https://brandsweets.com/colors/brands/warp-dev), Uber (https://brandsweets.com/colors/brands/uber-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #21c4bc in 4 real palettes, including Riot Games's brand system and Tiffany & Co.'s brand system, as the supporting colour. Seen in: Riot Games (https://brandsweets.com/colors/brands/riotgames-com), Tiffany & Co. (https://brandsweets.com/colors/brands/tiffany-com), DuckDuckGo (https://brandsweets.com/colors/brands/duckduckgo-com), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/crimson
- **Dodger Blue** #1e90ff [pool] — Designers have shipped Dodger Blue with #21c4bc: 4 real palettes, including Unity's brand system and Patreon's brand system, as the lead colour. Seen in: Unity (https://brandsweets.com/colors/brands/unity-com), Patreon (https://brandsweets.com/colors/brands/patreon-com), Figma (https://brandsweets.com/colors/brands/figma), Opensea (https://brandsweets.com/colors/brands/opensea-io). — https://brandsweets.com/colors/dodgerblue
- **Midnight Blue** #191970 [pool] — 6 real palettes, including Confluent's brand system and Ford's brand system put Midnight Blue beside #21c4bc, as the lead colour. Seen in: Confluent (https://brandsweets.com/colors/brands/confluent-io), Ford (https://brandsweets.com/colors/brands/ford-com), SoFi (https://brandsweets.com/colors/brands/sofi-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/midnightblue
- **Mustard Yellow** #ffdb58 [pool] — 4 real palettes, including Crayon Box and Fresh Juice put Mustard Yellow beside #21c4bc, as the accent. Seen in: Crayon Box (https://brandsweets.com/palettes/playful#crayon-box), Fresh Juice (https://brandsweets.com/palettes/playful#fresh-juice), Lido (https://brandsweets.com/palettes/vivid#lido), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/mustard
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #21c4bc in 5 real palettes, including Khan Academy's brand system and Docker's brand system, as the accent. Seen in: Khan Academy (https://brandsweets.com/colors/brands/khanacademy-org), Docker (https://brandsweets.com/colors/brands/docker-com), Brilliant (https://brandsweets.com/colors/brands/brilliant-org), Confluent (https://brandsweets.com/colors/brands/confluent-io). — https://brandsweets.com/colors/royalblue
- **Light Coral** #f08080 [harmony: complementary] — Light Coral sits directly opposite #21c4bc 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/lightcoral

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

- On white (#ffffff): 2.17:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #16837d (4.59:1); AA: background → #424242 (4.64:1); AAA: text → #10605c (7.37:1); AAA: background → #242424 (7.16:1)
- On black (#000000): 9.69:1 — 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/21c4bc-a2bcbe-d4599b-1f282d-e9f1ed?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: "#21c4bc" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.