# #21879c

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

## Values

- Hex: `#21879c`
- RGB: rgb(33, 135, 156)
- HSL: hsl(190, 65%, 37%)
- OKLCH: oklch(0.577 0.093 215.3)
- Relative luminance: 0.2005
- Nearest named color: Ahoy! Blue (#0082a1, Δ 2.179) — https://brandsweets.com/colors/ahoy-blue
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/21879c

## Tints & shades

- Tints (toward white): #269db5, #2cb3ce, #42bed7, #5bc7dc, #78d1e2, #92d9e8, #abe2ed, #c4ebf3, #ddf3f8, #f7fcfd
- Shades (toward black): #1e7c8f, #1b6e7e, #186372, #155865, #134d58, #0f3e48, #0c333b, #0a282e, #061a1d, #040f11

## Harmonies

- Complementary: #9c3521
- Analogous: #219c73, #214a9c
- Triadic: #9c2187, #879c21
- Split-complementary: #9c214a, #9c7321
- Tetradic: #73219c, #9c3521, #4a9c21

## Colors that go with #21879c

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 #21879c: softer than #000 and cool enough to feel like part of the same palette. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Auth0 (https://brandsweets.com/colors/brands/auth0-com), N26 (https://brandsweets.com/colors/brands/n26-com), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool). — https://brandsweets.com/colors/charcoal
- **Copper** #b87333 [harmony, pool: split] — Copper is a split-complement of #21879c: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Riverbed (https://brandsweets.com/palettes/muted#riverbed), Wellness (https://brandsweets.com/palettes/warm#wellness), Notion (https://brandsweets.com/colors/brands/notion), Atelier (https://brandsweets.com/palettes/elegant#atelier). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [harmony, pool: split] — Crimson is a split-complement of #21879c: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Redfin (https://brandsweets.com/colors/brands/redfin-com), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Wendy's (https://brandsweets.com/colors/brands/wendys-com), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/crimson
- **Rust** #b7410e [harmony, pool: complementary] — Rust sits directly opposite #21879c on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre), Gallery (https://brandsweets.com/palettes/editorial#gallery), Noir Beauty (https://brandsweets.com/palettes/dark#noir-beauty). — https://brandsweets.com/colors/rust
- **Amber** #ffbf00 [pool] — Amber is paired with #21879c in 4 real palettes, including Beach Hut and Wired's brand system, as the supporting colour. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Wired (https://brandsweets.com/colors/brands/wired-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com). — https://brandsweets.com/colors/amber
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #21879c: 6 real palettes, including Hershey's's brand system and Glacier, as the supporting colour. Seen in: Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/cobalt
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #21879c: 4 real palettes, including Deep Water and Telegram's brand system, as the lead colour. Seen in: Deep Water (https://brandsweets.com/palettes/dark#deep-water), Telegram (https://brandsweets.com/colors/brands/telegram-org), Astro (https://brandsweets.com/colors/brands/astro-build), Venmo (https://brandsweets.com/colors/brands/venmo-com). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #21879c: 15 real palettes, including Peacock and Discover's brand system, as the supporting colour. Seen in: Peacock (https://brandsweets.com/palettes/vivid#peacock), Discover (https://brandsweets.com/colors/brands/discover-com), Capital One (https://brandsweets.com/colors/brands/capitalone-com), Campus (https://brandsweets.com/palettes/friendly#campus). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 4.19:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #1f8093 (4.6:1); AA: background → #0f0f0f (4.57:1); AAA: text → #175f6d (7.26:1)
- On black (#000000): 5.01:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #28a4bd (7.14:1)

## 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/21879c-a2b6be-df4e7c-1f252d-e9f1ef?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: "#21879c" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.