# #421c59

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

## Values

- Hex: `#421c59`
- RGB: rgb(66, 28, 89)
- HSL: hsl(277, 52%, 23%)
- OKLCH: oklch(0.313 0.109 310.3)
- Relative luminance: 0.0271
- Nearest named color: Fading Horizon (#442266, Δ 2.611) — https://brandsweets.com/colors/fading-horizon
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/421c59

## Tints & shades

- Tints (toward white): #592678, #6d2f93, #8438b2, #9649c5, #a868cf, #b783d8, #c9a2e2, #d9bdea, #ebdcf4, #fbf7fd
- Shades (toward black): #3c1a51, #36174a, #311542, #2b123a, #281136, #220f2f, #1d0c27, #170a1f, #110717, #0b0510

## Harmonies

- Complementary: #34591c
- Analogous: #231c59, #591c52
- Triadic: #59421c, #1c5942
- Split-complementary: #52591c, #1c5923
- Tetradic: #59231c, #34591c, #1c5259

## Colors that go with #421c59

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 #421c59: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: complementary] — Sea Green sits directly opposite #421c59 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Subaru (https://brandsweets.com/colors/brands/subaru-com), Mushroom (https://brandsweets.com/palettes/neutral#mushroom), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/seagreen
- **Teal** #008080 [harmony, pool: triadic] — Teal completes a triad with #421c59 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Lufthansa (https://brandsweets.com/colors/brands/lufthansa-com), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Stanley (https://brandsweets.com/colors/brands/stanley1913-com), Alpine (https://brandsweets.com/palettes/cool#alpine). — https://brandsweets.com/colors/teal
- **Blue** #0000ff [pool] — 7 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #421c59, 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 #421c59: 6 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
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #421c59: 4 real palettes, including Blue Mono and Purina Pro Plan's brand system, as the lead colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), MLB (https://brandsweets.com/colors/brands/mlb-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #421c59: 4 real palettes, including Dusk and Clean Beauty, as the accent. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Clean Beauty (https://brandsweets.com/palettes/minimal#clean-beauty), Notion (https://brandsweets.com/colors/brands/notion), Bramble (https://brandsweets.com/palettes/muted#bramble). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #421c59 in 9 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

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

- On white (#ffffff): 13.62:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.54:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9c54c9 (4.53:1); AA: background → #969696 (4.6:1); AAA: text → #b783d8 (7.25:1); AAA: background → #bababa (7.02:1)

## 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/421c59-b99cc4-bdcb62-2d1f2c-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: "#421c59" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.