# #421e57

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

## Values

- Hex: `#421e57`
- RGB: rgb(66, 30, 87)
- HSL: hsl(278, 49%, 23%)
- OKLCH: oklch(0.315 0.103 311)
- Relative luminance: 0.0277
- Nearest named color: Fading Horizon (#442266, Δ 2.755) — https://brandsweets.com/colors/fading-horizon
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/421e57

## Tints & shades

- Tints (toward white): #592876, #6e3190, #853caf, #974cc2, #a96bcc, #b885d5, #caa4e0, #d9bee9, #ebddf3, #fbf7fc
- Shades (toward black): #3d1b50, #371948, #311641, #2b1439, #281235, #23102e, #1d0d26, #170a1e, #110817, #0c050f

## Harmonies

- Complementary: #33571e
- Analogous: #261e57, #571e50
- Triadic: #57421e, #1e5742
- Split-complementary: #50571e, #1e5726
- Tetradic: #57261e, #33571e, #1e5057

## Colors that go with #421e57

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 #421e57: 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), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: complementary] — Sea Green sits directly opposite #421e57 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 #421e57 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Mid-Century (https://brandsweets.com/palettes/warm#mid-century), Stanley (https://brandsweets.com/colors/brands/stanley1913-com), Lufthansa (https://brandsweets.com/colors/brands/lufthansa-com), Alpine (https://brandsweets.com/palettes/cool#alpine). — https://brandsweets.com/colors/teal
- **Blue** #0000ff [pool] — 8 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #421e57, 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 #421e57: 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 #421e57: 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), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), MLB (https://brandsweets.com/colors/brands/mlb-com). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #421e57: 5 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
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #421e57: 4 real palettes, including Blue Mono and Blizzard's brand system, as the supporting colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Blizzard (https://brandsweets.com/colors/brands/blizzard-com), Peacock (https://brandsweets.com/colors/brands/peacocktv-com), Retool (https://brandsweets.com/colors/brands/retool-com). — https://brandsweets.com/colors/cornflowerblue

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

- On white (#ffffff): 13.5:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.55:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9d58c6 (4.64:1); AA: background → #969696 (4.57:1); AAA: text → #b682d4 (7.13:1); 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/421e57-ba9cc4-bbcb62-2d1f2c-ebe9f1?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: "#421e57" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.