# #421d63

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

## Values

- Hex: `#421d63`
- RGB: rgb(66, 29, 99)
- HSL: hsl(272, 55%, 25%)
- OKLCH: oklch(0.323 0.119 304.8)
- Relative luminance: 0.0294
- Nearest named color: Fading Horizon (#442266, Δ 1.304) — https://brandsweets.com/colors/fading-horizon
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/421d63

## Tints & shades

- Tints (toward white): #55257e, #6a2e9e, #7c36ba, #8e49ca, #a269d3, #b384db, #c4a0e3, #d5bceb, #e9dbf5, #faf7fd
- Shades (toward black): #3d1a5b, #381853, #32164b, #2d1443, #28113b, #200e2f, #1a0b28, #150920, #100718, #0b0510

## Harmonies

- Complementary: #3d631d
- Analogous: #1f1d63, #631d60
- Triadic: #63421d, #1d6342
- Split-complementary: #60631d, #1d631f
- Tetradic: #631f1d, #3d631d, #1d6063

## Colors that go with #421d63

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 #421d63's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Confluent (https://brandsweets.com/colors/brands/confluent-io), Discord (https://brandsweets.com/colors/brands/discord), Docker (https://brandsweets.com/colors/brands/docker-com), Telehealth (https://brandsweets.com/palettes/modern#telehealth). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 4 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #421d63, as the accent. Seen in: Sketch (https://brandsweets.com/colors/brands/sketch-com), Monzo (https://brandsweets.com/colors/brands/monzo-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #421d63: 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
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #421d63: 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), Tumblr (https://brandsweets.com/colors/brands/tumblr-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [pool] — Crimson is paired with #421d63 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 #421d63: 16 real palettes, including Hinge's brand system and Panasonic's brand system, as the accent. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Discover (https://brandsweets.com/colors/brands/discover-com), Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com). — https://brandsweets.com/colors/denim
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #421d63 in 4 real palettes, including Tumblr's brand system and Audi's brand system, as the accent. Seen in: Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Audi (https://brandsweets.com/colors/brands/audi-com), Tide (https://brandsweets.com/colors/brands/tide-com), Monzo (https://brandsweets.com/colors/brands/monzo-com). — https://brandsweets.com/colors/orangered
- **Powder Blue** #b0e0e6 [pool] — Designers have shipped Powder Blue with #421d63: 6 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

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

- On white (#ffffff): 13.23:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.59:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9859cf (4.67:1); AA: background → #999999 (4.64:1); AAA: text → #b384db (7.24:1); AAA: background → #bdbdbd (7.04:1)

## 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/421d63-b69cc4-c5cb62-2d1f2d-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: "#421d63" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.