# #21fddf

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

## Values

- Hex: `#21fddf`
- RGB: rgb(33, 253, 223)
- HSL: hsl(172, 98%, 56%)
- OKLCH: oklch(0.892 0.158 179.8)
- Relative luminance: 0.759
- Nearest named color: Arctic Water (#00fcfc, Δ 4.13) — https://brandsweets.com/colors/arctic-water
- Moods: vivid
- Page: https://brandsweets.com/colors/21fddf

## Tints & shades

- Tints (toward white): #35fde2, #49fde5, #62fde9, #77feec, #8bfeee, #9ffef1, #b3fef4, #cdfef8, #e1fffb, #f5fffe
- Shades (toward black): #08fddc, #02e8ca, #02caaf, #02b199, #029783, #017e6e, #016558, #01473d, #002d27, #001412

## Harmonies

- Complementary: #fd213e
- Analogous: #21fd71, #21acfd
- Triadic: #df21fd, #fddf21
- Split-complementary: #fd21ac, #fd7121
- Tetradic: #7121fd, #fd213e, #acfd21

## Colors that go with #21fddf

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 #21fddf: softer than #000 and cool enough to feel like part of the same palette. Seen in: Canopy (https://brandsweets.com/palettes/cool#canopy), UEFA (https://brandsweets.com/colors/brands/uefa-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/charcoal
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #21fddf: 4 real palettes, including Astro's brand system and Prime Video's brand system, as the supporting colour. Seen in: Astro (https://brandsweets.com/colors/brands/astro-build), Prime Video (https://brandsweets.com/colors/brands/primevideo-com), Remix (https://brandsweets.com/colors/brands/remix-run), Salesforce (https://brandsweets.com/colors/brands/salesforce-com). — https://brandsweets.com/colors/deepskyblue
- **Light Coral** #f08080 [harmony: complementary] — Light Coral sits directly opposite #21fddf 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
- **Crimson** #dc143c [pool] — Crimson is paired with #21fddf in 3 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). — https://brandsweets.com/colors/crimson
- **Taupe** #483c32 [pool] — Taupe is paired with #21fddf in 3 real palettes, including Astro's brand system and Mint Chip, as the text colour against it. Seen in: 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: split] — Salmon is a split-complement of #21fddf: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. — https://brandsweets.com/colors/salmon
- **Violet** #ee82ee [harmony: split] — Violet is a split-complement of #21fddf: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. — https://brandsweets.com/colors/violet
- **Emerald Green** #50c878 [harmony, pool: analogous] — Emerald Green is #21fddf's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Supabase (https://brandsweets.com/colors/brands/supabase). — https://brandsweets.com/colors/emerald-green

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

- On white (#ffffff): 1.3:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #018372 (4.68:1); AA: background → #636363 (4.63:1); AAA: text → #016053 (7.5:1); AAA: background → #474747 (7.16:1)
- On black (#000000): 16.18:1 — 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/21fddf-a2bebe-d459a5-1f292d-e9f1ec?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: "#21fddf" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.