# #331d81

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

## Values

- Hex: `#331d81`
- RGB: rgb(51, 29, 129)
- HSL: hsl(253, 63%, 31%)
- OKLCH: oklch(0.333 0.156 284.2)
- Relative luminance: 0.0317
- Nearest named color: Deep Space Rodeo (#332277, Δ 1.913) — https://brandsweets.com/colors/deep-space-rodeo
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/331d81

## Tints & shades

- Tints (toward white): #3e249e, #482ab7, #5533d1, #6e50d7, #866ede, #9b86e4, #b3a4ea, #cbc1f1, #e0daf7, #f8f7fd
- Shades (toward black): #2e1a74, #2b196c, #261660, #211353, #1e114b, #190e3e, #140b32, #0f0825, #0b071d, #070411

## Harmonies

- Complementary: #6b811d
- Analogous: #1d3981, #651d81
- Triadic: #81331d, #1d8133
- Split-complementary: #81651d, #39811d
- Tetradic: #811d39, #6b811d, #1d8165

## Colors that go with #331d81

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Denim** #1560bd [harmony, pool: analogous] — Denim is #331d81's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com). — https://brandsweets.com/colors/denim
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #331d81: 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), CeraVe (https://brandsweets.com/colors/brands/cerave-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [pool] — Crimson is paired with #331d81 in 6 real palettes, including Casper Sleep's brand system and Nintendo's brand system, as the lead colour. Seen in: Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Pepsi (https://brandsweets.com/colors/brands/pepsi-com), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/crimson
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #331d81 in 4 real palettes, including Discord's brand system and Nivea's brand system, as the lead colour. Seen in: Discord (https://brandsweets.com/colors/brands/discord), Nivea (https://brandsweets.com/colors/brands/nivea-com), Confluent (https://brandsweets.com/colors/brands/confluent-io), Nokia (https://brandsweets.com/colors/brands/nokia-com). — https://brandsweets.com/colors/royalblue
- **Steel Blue** #4682b4 [pool] — Designers have shipped Steel Blue with #331d81: 6 real palettes, including FedEx's brand system and Hershey's's brand system, as the accent. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Taupe** #483c32 [pool] — Taupe is paired with #331d81 in 4 real palettes, including Gillette's brand system and Boeing's brand system, as the lead colour. Seen in: Gillette (https://brandsweets.com/colors/brands/gillette-com), Boeing (https://brandsweets.com/colors/brands/boeing-com), American Eagle (https://brandsweets.com/colors/brands/ae-com), Datadog (https://brandsweets.com/colors/brands/datadoghq-com). — https://brandsweets.com/colors/taupe
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #331d81 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
- **Blue** #0000ff [pool] — 3 real palettes, including Procter & Gamble's brand system and Alaska Airlines's brand system put Blue beside #331d81, as the supporting colour. Seen in: Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Zillow (https://brandsweets.com/colors/brands/zillow-com). — https://brandsweets.com/colors/blue

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

- On white (#ffffff): 12.86:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.63:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #7c61db (4.59:1); AA: background → #999999 (4.51:1); AAA: text → #9e8be5 (7.28:1); AAA: background → #c2c2c2 (7.22:1)

## 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/331d81-a99cc4-dfb84e-281f2d-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: "#331d81" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.