# #371f5b

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

## Values

- Hex: `#371f5b`
- RGB: rgb(55, 31, 91)
- HSL: hsl(264, 49%, 24%)
- OKLCH: oklch(0.305 0.103 298.5)
- Relative luminance: 0.0255
- Nearest named color: Fabric of Space (#341758, Δ 2.064) — https://brandsweets.com/colors/fabric-of-space
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/371f5b

## Tints & shades

- Tints (toward white): #472876, #5a3394, #6a3caf, #7e50c3, #926bcc, #a585d5, #bca4e0, #cfbee9, #e6ddf3, #f9f7fc
- Shades (toward black): #331d54, #2e1a4c, #291744, #25153d, #201235, #1c102e, #170d26, #120a1e, #0e0817, #09050f

## Harmonies

- Complementary: #435b1f
- Analogous: #1f255b, #551f5b
- Triadic: #5b371f, #1f5b37
- Split-complementary: #5b551f, #255b1f
- Tetradic: #5b1f25, #435b1f, #1f5b55

## Colors that go with #371f5b

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 #371f5b: softer than #000 and cool enough to feel like part of the same palette. Seen in: Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Squarespace (https://brandsweets.com/colors/brands/squarespace-com). — https://brandsweets.com/colors/charcoal
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #371f5b 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), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal), Cohere (https://brandsweets.com/colors/brands/cohere-com), Olive Grove (https://brandsweets.com/palettes/muted#olive-grove). — https://brandsweets.com/colors/darkolivegreen
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #371f5b'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), Telehealth (https://brandsweets.com/palettes/modern#telehealth), 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 #371f5b: 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), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Mushroom (https://brandsweets.com/palettes/neutral#mushroom). — https://brandsweets.com/colors/seagreen
- **Teal** #008080 [harmony, pool: triadic] — Teal completes a triad with #371f5b — 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), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Alpine (https://brandsweets.com/palettes/cool#alpine), Stanley (https://brandsweets.com/colors/brands/stanley1913-com). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #371f5b in 4 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] — 10 real palettes, including Sketch's brand system and Monzo's brand system put Blue beside #371f5b, as the accent. Seen in: Sketch (https://brandsweets.com/colors/brands/sketch-com), Monzo (https://brandsweets.com/colors/brands/monzo-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net), Headspace (https://brandsweets.com/colors/brands/headspace-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #371f5b: 7 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

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

- On white (#ffffff): 13.91:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.51:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #895fc8 (4.53:1); AA: background → #949494 (4.59:1); AAA: text → #a889d7 (7.22:1); AAA: background → #b8b8b8 (7.01:1)

## 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/371f5b-b19cc4-dfd34e-2b1f2d-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: "#371f5b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.