# #643ba5

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

## Values

- Hex: `#643ba5`
- RGB: rgb(100, 59, 165)
- HSL: hsl(263, 47%, 44%)
- OKLCH: oklch(0.458 0.163 297.3)
- Relative luminance: 0.0855
- Nearest named color: rebeccapurple (#663399, Δ 2.502) — https://brandsweets.com/colors/rebeccapurple
- Moods: cool, modern
- Page: https://brandsweets.com/colors/643ba5

## Tints & shades

- Tints (toward white): #6f42b8, #8056c2, #8e69c9, #9f80d1, #ad92d8, #bba5df, #ccbce7, #daceed, #ebe5f6, #f9f8fc
- Shades (toward black): #5b3696, #523187, #492b78, #402669, #36205a, #2d1b4b, #24163c, #1b102d, #120b1e, #09050f

## Harmonies

- Complementary: #7da53b
- Analogous: #3b48a5, #993ba5
- Triadic: #a5643b, #3ba564
- Split-complementary: #a5993b, #48a53b
- Tetradic: #a53b48, #7da53b, #3ba599

## Colors that go with #643ba5

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 #643ba5: 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), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Starlink (https://brandsweets.com/colors/brands/starlink-com). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #643ba5's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com), Guinness (https://brandsweets.com/colors/brands/guinness-com), Carrefour (https://brandsweets.com/colors/brands/carrefour-com). — https://brandsweets.com/colors/royalblue
- **Blue** #0000ff [pool] — 5 real palettes, including Zillow's brand system and Pixar's brand system put Blue beside #643ba5, as the lead colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), Pixar (https://brandsweets.com/colors/brands/pixar-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #643ba5 in 8 real palettes, including Wells Fargo's brand system and Gemstone, as the lead colour. Seen in: Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Netflix (https://brandsweets.com/colors/brands/netflix). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #643ba5: 7 real palettes, including Slack's brand system and Linkedin's brand system, as the lead colour. Seen in: Slack (https://brandsweets.com/colors/brands/slack-com), Linkedin (https://brandsweets.com/colors/brands/linkedin-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/denim
- **Midnight Blue** #191970 [pool] — 9 real palettes, including Kraken's brand system and Blue Mono put Midnight Blue beside #643ba5, as the lead colour. Seen in: Kraken (https://brandsweets.com/colors/brands/kraken-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/midnightblue
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #643ba5: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Taupe** #483c32 [pool] — Taupe is paired with #643ba5 in 4 real palettes, including Datadog's brand system and Superhuman's brand system, as that palette's text colour. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), Superhuman (https://brandsweets.com/colors/brands/superhuman-com), Nikon (https://brandsweets.com/colors/brands/nikon-com), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/taupe

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

- On white (#ffffff): 7.75:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.71:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8862c6 (4.61:1); AA: background → #c7c7c7 (4.58:1); AAA: text → #a78bd5 (7.3:1); AAA: background → #f5f5f5 (7.11:1)

## Fonts for this mood

- 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/643ba5-b09cc4-dfd04e-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: "#643ba5" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.