# #643399

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

## Values

- Hex: `#643399`
- RGB: rgb(100, 51, 153)
- HSL: hsl(269, 50%, 40%)
- OKLCH: oklch(0.438 0.16 302.3)
- Relative luminance: 0.0738
- Nearest named color: rebeccapurple (#663399, Δ 0.392) — https://brandsweets.com/colors/rebeccapurple
- Moods: cool, modern
- Page: https://brandsweets.com/colors/643399

## Tints & shades

- Tints (toward white): #733bb0, #8347c2, #905bc8, #9f71d0, #af88d7, #be9fdf, #ceb6e7, #dbc9ed, #eae0f5, #faf7fc
- Shades (toward black): #5a2e8a, #532a7e, #49256f, #412163, #371c54, #2d1745, #261339, #1c0e2a, #140a1f, #0a050f

## Harmonies

- Complementary: #689933
- Analogous: #333599, #973399
- Triadic: #996433, #339964
- Split-complementary: #999733, #359933
- Tetradic: #993335, #689933, #339997

## Colors that go with #643399

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

- **Crimson** #dc143c [pool] — Crimson is paired with #643399 in 4 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), Lenovo (https://brandsweets.com/colors/brands/lenovo-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #643399: 4 real palettes, including Slack's brand system and Hinge's brand system, as the lead colour. Seen in: Slack (https://brandsweets.com/colors/brands/slack-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), Linkedin (https://brandsweets.com/colors/brands/linkedin-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com). — https://brandsweets.com/colors/denim
- **Midnight Blue** #191970 [pool] — 4 real palettes, including Kraken's brand system and Blue Mono put Midnight Blue beside #643399, as the lead colour. Seen in: Kraken (https://brandsweets.com/colors/brands/kraken-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), First Snow (https://brandsweets.com/palettes/cool#first-snow), Panasonic (https://brandsweets.com/colors/brands/panasonic-com). — https://brandsweets.com/colors/midnightblue
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #643399'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), Nokia (https://brandsweets.com/colors/brands/nokia-com). — https://brandsweets.com/colors/royalblue
- **Tomato** #ff6347 [pool] — 6 real palettes, including FedEx's brand system and GitLab's brand system put Tomato beside #643399, as the supporting colour. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), GitLab (https://brandsweets.com/colors/brands/gitlab), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com). — https://brandsweets.com/colors/tomato
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #643399 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
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #643399: 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). — https://brandsweets.com/colors/charcoal
- **Taupe** #483c32 [pool] — Taupe is paired with #643399 in 3 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), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/taupe

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

- On white (#ffffff): 8.48:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.48:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #905bc8 (4.52:1); AA: background → #bdbdbd (4.52:1); AAA: text → #ac85d6 (7.08:1); AAA: background → #ebebeb (7.12:1)

## Brands using this color

- **Ledger** — secondary #6a3794 (Δ 1.795) — https://brandsweets.com/colors/brands/ledger-com

## 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/643399-b49cc4-cbcb62-2c1f2d-e9e9f1?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: "#643399" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.