# #421b5f

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

## Values

- Hex: `#421b5f`
- RGB: rgb(66, 27, 95)
- HSL: hsl(274, 56%, 24%)
- OKLCH: oklch(0.317 0.117 307.3)
- Relative luminance: 0.0277
- Nearest named color: Fading Horizon (#442266, Δ 1.98) — https://brandsweets.com/colors/fading-horizon
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/421b5f

## Tints & shades

- Tints (toward white): #55237b, #6b2c9b, #7e34b7, #9248cb, #a364d3, #b380db, #c6a0e4, #d7bbec, #eadbf5, #faf7fd
- Shades (toward black): #3c1958, #371650, #311448, #2c1240, #261038, #210d30, #1b0b28, #160920, #100718, #0b0410

## Harmonies

- Complementary: #395f1b
- Analogous: #1f1b5f, #5f1b5b
- Triadic: #5f421b, #1b5f42
- Split-complementary: #5b5f1b, #1b5f1f
- Tetradic: #5f1f1b, #395f1b, #1b5b5f

## Colors that go with #421b5f

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 #421b5f: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com). — https://brandsweets.com/colors/charcoal
- **Blue** #0000ff [pool] — 4 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #421b5f, as the accent. Seen in: Sketch (https://brandsweets.com/colors/brands/sketch-com), Monzo (https://brandsweets.com/colors/brands/monzo-com), Tim Hortons (https://brandsweets.com/colors/brands/timhortons-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #421b5f: 4 real palettes, including SoFi's brand system and Open House, as the supporting colour. Seen in: SoFi (https://brandsweets.com/colors/brands/sofi-com), Open House (https://brandsweets.com/palettes/clean#open-house), Coastal (https://brandsweets.com/palettes/cool#coastal), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/cadetblue
- **Crimson** #dc143c [pool] — Crimson is paired with #421b5f in 5 real palettes, including Marvel's brand system and Casper Sleep's brand system, as the accent. Seen in: Marvel (https://brandsweets.com/colors/brands/marvel-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Nintendo (https://brandsweets.com/colors/brands/nintendo-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #421b5f: 14 real palettes, including Discover's brand system and Hinge's brand system, as the supporting colour. Seen in: Discover (https://brandsweets.com/colors/brands/discover-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Open House (https://brandsweets.com/palettes/clean#open-house). — https://brandsweets.com/colors/denim
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #421b5f in 4 real palettes, including Audi's brand system and Tumblr's brand system, as the accent. Seen in: Audi (https://brandsweets.com/colors/brands/audi-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Monzo (https://brandsweets.com/colors/brands/monzo-com), Tide (https://brandsweets.com/colors/brands/tide-com). — https://brandsweets.com/colors/orangered
- **Powder Blue** #b0e0e6 [pool] — Designers have shipped Powder Blue with #421b5f: 5 real palettes, including Frost & Ember and Macaron, as the supporting colour. Seen in: Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Macaron (https://brandsweets.com/palettes/light#macaron), Sorbet (https://brandsweets.com/palettes/light#sorbet), Opera (https://brandsweets.com/colors/brands/opera-com). — https://brandsweets.com/colors/powderblue
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #421b5f 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/olive

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

- On white (#ffffff): 13.52:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.55:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9a54cf (4.54:1); AA: background → #969696 (4.57:1); AAA: text → #b380db (7.03:1); AAA: background → #bdbdbd (7.19:1)

## Fonts for this mood

- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold
- 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/421b5f-b79cc4-c2cb62-2d1f2d-eae9f1?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: "#421b5f" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.