# #331b65

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

## Values

- Hex: `#331b65`
- RGB: rgb(51, 27, 101)
- HSL: hsl(259, 58%, 25%)
- OKLCH: oklch(0.303 0.122 292.4)
- Relative luminance: 0.0243
- Nearest named color: Dark Dreams (#332266, Δ 1.594) — https://brandsweets.com/colors/dark-dreams
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/331b65

## Tints & shades

- Tints (toward white): #402281, #502ba1, #5e32bd, #7146ce, #8966d6, #9f82de, #b59ee5, #cabbed, #e3dbf5, #f9f7fd
- Shades (toward black): #2e195d, #2a1655, #26144d, #221244, #1e103c, #180d30, #140b28, #100920, #0c0618, #080410

## Harmonies

- Complementary: #4d651b
- Analogous: #1b2865, #571b65
- Triadic: #65321b, #1b6532
- Split-complementary: #65571b, #28651b
- Tetradic: #651b28, #4d651b, #1b6557

## Colors that go with #331b65

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 #331b65: softer than #000 and cool enough to feel like part of the same palette. Seen in: CeraVe (https://brandsweets.com/colors/brands/cerave-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Microsoft (https://brandsweets.com/colors/brands/microsoft-com). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #331b65's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Discord (https://brandsweets.com/colors/brands/discord), Confluent (https://brandsweets.com/colors/brands/confluent-io), Telehealth (https://brandsweets.com/palettes/modern#telehealth), GEICO (https://brandsweets.com/colors/brands/geico-com). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 4 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #331b65, 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), Penpot (https://brandsweets.com/colors/brands/penpot-app). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #331b65: 5 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 #331b65: 5 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), MLB (https://brandsweets.com/colors/brands/mlb-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #331b65 in 5 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour. Seen in: Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #331b65: 14 real palettes, including Bank of America's brand system and Panasonic's brand system, as the accent. Seen in: Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Discover (https://brandsweets.com/colors/brands/discover-com), Skechers (https://brandsweets.com/colors/brands/skechers-com). — https://brandsweets.com/colors/denim
- **Light Pink** #ffb6c1 [pool] — Light Pink shows up next to #331b65 in 4 real palettes, including Railway's brand system and Macaron, as the supporting colour. Seen in: Railway (https://brandsweets.com/colors/brands/railway-app), Macaron (https://brandsweets.com/palettes/light#macaron), Sorbet (https://brandsweets.com/palettes/light#sorbet), Pastel Pop (https://brandsweets.com/palettes/playful#pastel-pop). — https://brandsweets.com/colors/lightpink

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

- On white (#ffffff): 14.14:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.49:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #835ed4 (4.52:1); AA: background → #949494 (4.66:1); AAA: text → #a286df (7.01:1); AAA: background → #b8b8b8 (7.13:1)

## Brands using this color

- **Kraken** — primary #331469 (Δ 1.473) — https://brandsweets.com/colors/brands/kraken-com

## 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/331b65-ad9cc4-dfc74e-2a1f2d-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: "#331b65" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.