# #421d9f

A color — cool, vivid, technical, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#421d9f`
- RGB: rgb(66, 29, 159)
- HSL: hsl(257, 69%, 37%)
- OKLCH: oklch(0.379 0.19 286.1)
- Relative luminance: 0.0454
- Nearest named color: Galactic Civilization (#442288, Δ 3.92) — https://brandsweets.com/colors/galactic-civilization
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/421d9f

## Tints & shades

- Tints (toward white): #4d22b9, #5827d3, #6a3ddb, #7e57e0, #9575e6, #a98fea, #bda9ef, #d1c3f4, #e5ddf9, #f8f6fd
- Shades (toward black): #3d1b93, #361881, #301574, #2b1367, #26115a, #1e0d49, #190b3c, #14092f, #0d061e, #070311

## Harmonies

- Complementary: #7b9f1d
- Analogous: #1d399f, #831d9f
- Triadic: #9f421d, #1d9f42
- Split-complementary: #9f831d, #399f1d
- Tetradic: #9f1d39, #7b9f1d, #1d9f83

## Colors that go with #421d9f

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 #421d9f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Nivea (https://brandsweets.com/colors/brands/nivea-com), Discord (https://brandsweets.com/colors/brands/discord), Nokia (https://brandsweets.com/colors/brands/nokia-com), NHL (https://brandsweets.com/colors/brands/nhl-com). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 4 real palettes, including Zillow's brand system and Procter & Gamble's brand system put Blue beside #421d9f, as the lead colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Pfizer (https://brandsweets.com/colors/brands/pfizer-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #421d9f in 7 real palettes, including Pepsi's brand system and Walgreens's brand system, as the supporting colour. Seen in: Pepsi (https://brandsweets.com/colors/brands/pepsi-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #421d9f: 4 real palettes, including Warbyparker's brand system and Unilever's brand system, as the accent. Seen in: Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Unilever (https://brandsweets.com/colors/brands/unilever-com), Slack (https://brandsweets.com/colors/brands/slack-com), Intel (https://brandsweets.com/colors/brands/intel-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #421d9f: 4 real palettes, including Datadog's brand system and 3M's brand system, as the accent. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), 3M (https://brandsweets.com/colors/brands/3m-com), MLB (https://brandsweets.com/colors/brands/mlb-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com). — https://brandsweets.com/colors/firebrick
- **Midnight Blue** #191970 [pool] — 8 real palettes, including Kraken's brand system and Blue Mono put Midnight Blue beside #421d9f, as the lead colour. Seen in: Kraken (https://brandsweets.com/colors/brands/kraken-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Air France (https://brandsweets.com/colors/brands/airfrance-com). — https://brandsweets.com/colors/midnightblue
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #421d9f 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
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #421d9f: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Boeing (https://brandsweets.com/colors/brands/boeing-com). — https://brandsweets.com/colors/charcoal

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

- On white (#ffffff): 11.01:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.91:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #815be1 (4.52:1); AA: background → #a6a6a6 (4.52:1); AAA: text → #a286e9 (7.12:1); AAA: background → #cfcfcf (7.06:1)

## Brands using this color

- **dbt Labs** — accent #3d189a (Δ 1.551) — https://brandsweets.com/colors/brands/getdbt-com

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- 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/421d9f-ac9cc4-dfc24e-291f2d-e9ebf1?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: "#421d9f" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.