# #21587d

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

## Values

- Hex: `#21587d`
- RGB: rgb(33, 88, 125)
- HSL: hsl(204, 58%, 31%)
- OKLCH: oklch(0.442 0.084 241.8)
- Relative luminance: 0.0878
- Nearest named color: Beyond the Sea (#005784, Δ 1.919) — https://brandsweets.com/colors/beyond-the-sea
- Moods: cool, modern
- Page: https://brandsweets.com/colors/21587d

## Tints & shades

- Tints (toward white): #296c99, #2f7db1, #3a91cb, #56a0d2, #72b0da, #8abee0, #a6cde7, #c3ddef, #dbebf5, #f7fafd
- Shades (toward black): #1e5071, #1c4a69, #19415d, #153951, #133349, #102b3c, #0d2230, #0a1a24, #07141c, #040b10

## Harmonies

- Complementary: #7d4621
- Analogous: #217d74, #212a7d
- Triadic: #7d2158, #587d21
- Split-complementary: #7d212a, #7d7421
- Tetradic: #74217d, #7d4621, #2a7d21

## Colors that go with #21587d

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

- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #21587d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Motorola (https://brandsweets.com/colors/brands/motorola-com), Stripe (https://brandsweets.com/colors/brands/stripe), Carrefour (https://brandsweets.com/colors/brands/carrefour-com), Zoom (https://brandsweets.com/colors/brands/zoom-us). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 7 real palettes, including Tesco's brand system and CVS's brand system put Blue beside #21587d, as the supporting colour. Seen in: Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Activision (https://brandsweets.com/colors/brands/activision-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #21587d: 4 real palettes, including Open House and Dusk, as the supporting colour. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Dusk (https://brandsweets.com/palettes/cool#dusk), Alpine (https://brandsweets.com/palettes/cool#alpine), Paper & Pine (https://brandsweets.com/palettes/minimal#paper-and-pine). — https://brandsweets.com/colors/cadetblue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #21587d: 4 real palettes, including Coca-Cola's brand system and Blue Mono, as the supporting colour. Seen in: Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Gopro (https://brandsweets.com/colors/brands/gopro-com), Blizzard (https://brandsweets.com/colors/brands/blizzard-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #21587d in 16 real palettes, including Codecademy's brand system and Walgreens's brand system, as the accent. Seen in: Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Costco (https://brandsweets.com/colors/brands/costco-com), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #21587d: 15 real palettes, including HP's brand system and Dutch Bros's brand system, as the accent. Seen in: HP (https://brandsweets.com/colors/brands/hp-com), Dutch Bros (https://brandsweets.com/colors/brands/dutchbros-com), The New York Times (https://brandsweets.com/colors/brands/nytimes-com), Unilever (https://brandsweets.com/colors/brands/unilever-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #21587d: 4 real palettes, including Fireside and Wendy's's brand system, as the lead colour. Seen in: Fireside (https://brandsweets.com/palettes/dark#fireside), Wendy's (https://brandsweets.com/colors/brands/wendys-com), AT&T (https://brandsweets.com/colors/brands/att-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com). — https://brandsweets.com/colors/firebrick
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #21587d: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy. — https://brandsweets.com/colors/whitesmoke

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

- On white (#ffffff): 7.62:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.76:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #2e7aad (4.5:1); AA: background → #c7c7c7 (4.51:1); AAA: text → #529ed1 (7.17:1); AAA: background → #f7f7f7 (7.11:1)

## Fonts for this mood

- 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/21587d-9cafc4-df4e5a-1f222d-e9f1f0?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: "#21587d" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.