# #21eefd

A color — cool, vivid, technical, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#21eefd`
- RGB: rgb(33, 238, 253)
- HSL: hsl(184, 98%, 56%)
- OKLCH: oklch(0.866 0.144 203.2)
- Relative luminance: 0.6856
- Nearest named color: Aqua (#0ff0fe, Δ 0.532) — https://brandsweets.com/colors/aqua-2
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/21eefd

## Tints & shades

- Tints (toward white): #35f0fd, #49f1fd, #62f3fd, #77f5fe, #8bf6fe, #9ff8fe, #b3f9fe, #cdfbfe, #e1fdff, #f5feff
- Shades (toward black): #08ecfd, #02d9e8, #02bdca, #02a5b1, #028d97, #01767e, #015e65, #014247, #002a2d, #001314

## Harmonies

- Complementary: #fd3021
- Analogous: #21fd9d, #2180fd
- Triadic: #fd21ee, #eefd21
- Split-complementary: #fd2180, #fd9d21
- Tetradic: #9d21fd, #fd3021, #80fd21

## Colors that go with #21eefd

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 #21eefd: softer than #000 and cool enough to feel like part of the same palette. Seen in: UEFA (https://brandsweets.com/colors/brands/uefa-com), Vimeo (https://brandsweets.com/colors/brands/vimeo-com), Boeing (https://brandsweets.com/colors/brands/boeing-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/charcoal
- **Deep Sky Blue** #00bfff [harmony, pool: analogous] — Deep Sky Blue is #21eefd's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Salesforce (https://brandsweets.com/colors/brands/salesforce-com), Astro (https://brandsweets.com/colors/brands/astro-build), Mistral AI (https://brandsweets.com/colors/brands/mistral-ai), Calendly (https://brandsweets.com/colors/brands/calendly-com). — https://brandsweets.com/colors/deepskyblue
- **Crimson** #dc143c [pool] — Crimson is paired with #21eefd in 4 real palettes, including Formula 1's brand system and Tiffany & Co.'s brand system, as the supporting colour. Seen in: Formula 1 (https://brandsweets.com/colors/brands/formula1-com), Tiffany & Co. (https://brandsweets.com/colors/brands/tiffany-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Riot Games (https://brandsweets.com/colors/brands/riotgames-com). — https://brandsweets.com/colors/crimson
- **Taupe** #483c32 [pool] — Taupe is paired with #21eefd in 7 real palettes, including Boeing's brand system and Astro's brand system, as the text colour against it. Seen in: Boeing (https://brandsweets.com/colors/brands/boeing-com), Astro (https://brandsweets.com/colors/brands/astro-build), Mint Chip (https://brandsweets.com/palettes/light#mint-chip), Macaron (https://brandsweets.com/palettes/light#macaron). — https://brandsweets.com/colors/taupe
- **Salmon** #fa8072 [harmony: complementary] — Salmon sits directly opposite #21eefd 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/salmon
- **Dark Orange** #ff8c00 [harmony, pool: split] — Dark Orange is a split-complement of #21eefd: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: PayPal (https://brandsweets.com/colors/brands/paypal-com). — https://brandsweets.com/colors/darkorange
- **Dodger Blue** #1e90ff [pool] — Designers have shipped Dodger Blue with #21eefd: 3 real palettes, including Bluesky Social's brand system and Opensea's brand system, as the lead colour. Seen in: Bluesky Social (https://brandsweets.com/colors/brands/bsky-app), Opensea (https://brandsweets.com/colors/brands/opensea-io), Patreon (https://brandsweets.com/colors/brands/patreon-com). — https://brandsweets.com/colors/dodgerblue
- **Light Pink** #ffb6c1 [pool] — Light Pink shows up next to #21eefd in 3 real palettes, including Macaron and Pastel Pop, as the lead colour. Seen in: Macaron (https://brandsweets.com/palettes/light#macaron), Pastel Pop (https://brandsweets.com/palettes/playful#pastel-pop), Sorbet (https://brandsweets.com/palettes/light#sorbet). — https://brandsweets.com/colors/lightpink

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

- On white (#ffffff): 1.43:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #017f88 (4.78:1); AA: background → #5e5e5e (4.54:1); AAA: text → #01636a (7.01:1); AAA: background → #424242 (7.04:1)
- On black (#000000): 14.71:1 — AA pass, AA-large pass, AAA pass

## Curated palettes containing it

- **Arcade** (neon, vivid, dark, bold) — #ff2e88, #00f0ff, #faff00, #0a0a14, #f5f5ff — Hot pink, cyan and acid yellow on near-black — cabinet-glow neon; the black surface is what makes the colours light up. — tool: https://brandsweets.com/palettes/new/ff2e88-00f0ff-faff00-0a0a14-f5f5ff — collection: https://brandsweets.com/palettes/neon

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/21eefd-a2b9be-df4e8a-1f262d-e9f1ee?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: "#21eefd" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.