# #21253b

A color — cool, muted, dark, luxury, bold. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#21253b`
- RGB: rgb(33, 37, 59)
- HSL: hsl(231, 28%, 18%)
- OKLCH: oklch(0.272 0.041 275.4)
- Relative luminance: 0.0196
- Nearest named color: Midnight Express (#21263a, Δ 0.43) — https://brandsweets.com/colors/midnight-express
- Moods: cool, muted, dark, luxury, bold
- Page: https://brandsweets.com/colors/21253b

## Tints & shades

- Tints (toward white): #303555, #3e466f, #4d5689, #5c67a3, #767fb2, #9097c1, #aab0cf, #c4c8de, #dee1ed, #f8f9fb
- Shades (toward black): #1f2337, #1c1f31, #1a1d2e, #161927, #141724, #121521, #0f101a, #0d0e17, #090a10, #07080d

## Harmonies

- Complementary: #3b3721
- Analogous: #21323b, #2a213b
- Triadic: #3b2125, #253b21
- Split-complementary: #3b2a21, #323b21
- Tetradic: #3b2132, #3b3721, #213b2a

## Colors that go with #21253b

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 #21253b: softer than #000 and cool enough to feel like part of the same palette. Seen in: Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool), Volkswagen (https://brandsweets.com/colors/brands/vw-com), Boeing (https://brandsweets.com/colors/brands/boeing-com). — https://brandsweets.com/colors/charcoal
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #21253b on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: 7-Eleven (https://brandsweets.com/colors/brands/7-eleven-com), Cohere (https://brandsweets.com/colors/brands/cohere-com), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal), Clay & Linen (https://brandsweets.com/palettes/warm#clay-and-linen). — https://brandsweets.com/colors/darkolivegreen
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #21253b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Subaru (https://brandsweets.com/colors/brands/subaru-com), Asana (https://brandsweets.com/colors/brands/asana-com), Wellness (https://brandsweets.com/palettes/warm#wellness), Mushroom (https://brandsweets.com/palettes/neutral#mushroom). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: split] — Sienna is a split-complement of #21253b: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Olive Grove (https://brandsweets.com/palettes/muted#olive-grove), Woodsmoke (https://brandsweets.com/palettes/dark#woodsmoke), BrandSweets (https://brandsweets.com/colors/brands/brandsweets), Harvest (https://brandsweets.com/palettes/warm#harvest). — https://brandsweets.com/colors/sienna
- **Slate Blue** #6a5acd [harmony, pool: analogous] — Slate Blue is #21253b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Superhuman (https://brandsweets.com/colors/brands/superhuman-com), GitLab (https://brandsweets.com/colors/brands/gitlab), Indigo SaaS (https://brandsweets.com/palettes/modern#indigo-saas), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/slateblue
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #21253b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Discover (https://brandsweets.com/colors/brands/discover-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #21253b in 18 real palettes, including Beach Hut and McDonald's's brand system, as the supporting colour. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 24 real palettes, including Monzo's brand system and Sketch's brand system put Blue beside #21253b, as the accent. Seen in: Monzo (https://brandsweets.com/colors/brands/monzo-com), Sketch (https://brandsweets.com/colors/brands/sketch-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Rolex (https://brandsweets.com/colors/brands/rolex-com). — https://brandsweets.com/colors/blue

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

- On white (#ffffff): 15.08:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.39:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6973ab (4.64:1); AA: background → #8f8f8f (4.66:1); AAA: text → #8d94bf (7.12:1); AAA: background → #b3b3b3 (7.19:1)

## Brands using this color

- **Discover** — primary #23233f (Δ 1.159) — https://brandsweets.com/colors/brands/discover-com
- **dbt Labs** — secondary #1e2939 (Δ 1.548) — https://brandsweets.com/colors/brands/getdbt-com
- **Microsoft** — accent #17253d (Δ 1.55) — https://brandsweets.com/colors/brands/microsoft-com
- **Nespresso** — primary #1f2533 (Δ 1.592) — https://brandsweets.com/colors/brands/nespresso-com
- **Volkswagen** — primary #1b2236 (Δ 1.691) — https://brandsweets.com/colors/brands/vw-com
- **Opera** — accent #252836 (Δ 1.742) — https://brandsweets.com/colors/brands/opera-com
- **Character** — secondary #1f2937 (Δ 1.754) — https://brandsweets.com/colors/brands/character-ai

## Curated palettes containing it

- **Campus** (friendly, cool, clean) — #1d4ed8, #64748b, #f59e0b, #ffffff, #1e293b — Institutional blue with a highlighter-amber accent — trustworthy for parents, lively enough for students. — tool: https://brandsweets.com/palettes/new/1d4ed8-64748b-f59e0b-ffffff-1e293b — collection: https://brandsweets.com/palettes/friendly
- **Open House** (clean, cool, modern) — #2f6690, #8fa3b8, #e3a72f, #ffffff, #1b2a41 — Steel blue for trust, warm gold for the sold moment — an approachable brokerage that still feels established. — tool: https://brandsweets.com/palettes/new/2f6690-8fa3b8-e3a72f-ffffff-1b2a41 — collection: https://brandsweets.com/palettes/clean
- **Tide Pool** (ocean, cool, light, clean) — #1b998b, #2d3047, #ff9b71, #f4fbf9, #1e2333 — Sea-green and slate with a coral — a literal tide pool: two cool tones, one warm creature. — tool: https://brandsweets.com/palettes/new/1b998b-2d3047-ff9b71-f4fbf9-1e2333 — collection: https://brandsweets.com/palettes/ocean

## Fonts for this mood

- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/21253b-9c9ec4-df834e-231f2d-e9eef1?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: "#21253b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.