# #331b50

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

## Values

- Hex: `#331b50`
- RGB: rgb(51, 27, 80)
- HSL: hsl(267, 50%, 21%)
- OKLCH: oklch(0.285 0.094 301.6)
- Relative luminance: 0.0207
- Nearest named color: Fabric of Space (#341758, Δ 1.747) — https://brandsweets.com/colors/fabric-of-space
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/331b50

## Tints & shades

- Tints (toward white): #46256f, #572e8a, #6b38a8, #7e47c2, #9466cc, #a781d5, #bc9fdf, #d1bee9, #e4d9f2, #faf7fc
- Shades (toward black): #2e1849, #2c1745, #27143d, #221236, #1f1132, #1b0e2a, #160b22, #11091b, #0f0817, #0a050f

## Harmonies

- Complementary: #38501b
- Analogous: #1b1d50, #4e1b50
- Triadic: #50331b, #1b5033
- Split-complementary: #504e1b, #1d501b
- Tetradic: #501b1d, #38501b, #1b504e

## Colors that go with #331b50

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 #331b50: softer than #000 and cool enough to feel like part of the same palette. Seen in: Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Volkswagen (https://brandsweets.com/colors/brands/vw-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), CeraVe (https://brandsweets.com/colors/brands/cerave-com). — https://brandsweets.com/colors/charcoal
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #331b50 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: 7-Eleven (https://brandsweets.com/colors/brands/7-eleven-com), Cohere (https://brandsweets.com/colors/brands/cohere-com), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal), Warp (https://brandsweets.com/colors/brands/warp-dev). — https://brandsweets.com/colors/darkolivegreen
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #331b50's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Telehealth (https://brandsweets.com/palettes/modern#telehealth), GEICO (https://brandsweets.com/colors/brands/geico-com), Confluent (https://brandsweets.com/colors/brands/confluent-io), Docker (https://brandsweets.com/colors/brands/docker-com). — https://brandsweets.com/colors/royalblue
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #331b50: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Subaru (https://brandsweets.com/colors/brands/subaru-com), Wellness (https://brandsweets.com/palettes/warm#wellness), Mushroom (https://brandsweets.com/palettes/neutral#mushroom). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: triadic] — Sienna completes a triad with #331b50 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Olive Grove (https://brandsweets.com/palettes/muted#olive-grove), Woodsmoke (https://brandsweets.com/palettes/dark#woodsmoke), Harvest (https://brandsweets.com/palettes/warm#harvest), BrandSweets (https://brandsweets.com/colors/brands/brandsweets). — https://brandsweets.com/colors/sienna
- **Teal** #008080 [harmony, pool: triadic] — Teal completes a triad with #331b50 — 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), Alpine (https://brandsweets.com/palettes/cool#alpine), Mid-Century (https://brandsweets.com/palettes/warm#mid-century), Clinic (https://brandsweets.com/palettes/clean#clinic). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #331b50 in 7 real palettes, including Southwest Airlines's brand system and Beach Hut, as the accent. Seen in: Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 15 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #331b50, as the accent. Seen in: Sketch (https://brandsweets.com/colors/brands/sketch-com), Monzo (https://brandsweets.com/colors/brands/monzo-com), Penpot (https://brandsweets.com/colors/brands/penpot-app), Readymag (https://brandsweets.com/colors/brands/readymag-com). — https://brandsweets.com/colors/blue

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

- On white (#ffffff): 14.86:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.41:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8f5ec9 (4.61:1); AA: background → #8f8f8f (4.59:1); AAA: text → #a985d6 (7.01:1); AAA: background → #b3b3b3 (7.09:1)

## 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/331b50-b39cc4-dfda4e-2c1f2d-e9eaf1?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: "#331b50" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.