# #643cb4

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

## Values

- Hex: `#643cb4`
- RGB: rgb(100, 60, 180)
- HSL: hsl(260, 50%, 47%)
- OKLCH: oklch(0.472 0.18 293.6)
- Relative luminance: 0.0924
- Nearest named color: rebeccapurple (#663399, Δ 4.68) — https://brandsweets.com/colors/rebeccapurple
- Moods: cool, modern
- Page: https://brandsweets.com/colors/643cb4

## Tints & shades

- Tints (toward white): #7047c2, #7f5bc8, #8e6ecf, #9d81d5, #af98dd, #beabe3, #ccbee9, #dbd1f0, #eae4f6, #f9f7fc
- Shades (toward black): #5b37a4, #513091, #482b82, #402673, #372163, #2d1b50, #241641, #1c1132, #110a1f, #08050f

## Harmonies

- Complementary: #8cb43c
- Analogous: #3c50b4, #a03cb4
- Triadic: #b4643c, #3cb464
- Split-complementary: #b4a03c, #50b43c
- Tetradic: #b43c50, #8cb43c, #3cb4a0

## Colors that go with #643cb4

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 #643cb4: softer than #000 and cool enough to feel like part of the same palette. Seen in: 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), UEFA (https://brandsweets.com/colors/brands/uefa-com). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #643cb4'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), NHL (https://brandsweets.com/colors/brands/nhl-com). — https://brandsweets.com/colors/royalblue
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #643cb4: 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), Intel (https://brandsweets.com/colors/brands/intel-com). — https://brandsweets.com/colors/seagreen
- **Crimson** #dc143c [pool] — Crimson is paired with #643cb4 in 10 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), Netflix (https://brandsweets.com/colors/brands/netflix), Ulta Beauty (https://brandsweets.com/colors/brands/ulta-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #643cb4: 9 real palettes, including Linkedin's brand system and Slack's brand system, as the lead colour. Seen in: Linkedin (https://brandsweets.com/colors/brands/linkedin-com), Slack (https://brandsweets.com/colors/brands/slack-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Unilever (https://brandsweets.com/colors/brands/unilever-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #643cb4: 4 real palettes, including Datadog's brand system and Campbell's's brand system, as the accent. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com), MLB (https://brandsweets.com/colors/brands/mlb-com), Nissan (https://brandsweets.com/colors/brands/nissanusa-com). — https://brandsweets.com/colors/firebrick
- **Midnight Blue** #191970 [pool] — 10 real palettes, including Kraken's brand system and Paramount+'s brand system put Midnight Blue beside #643cb4, as the lead colour. Seen in: Kraken (https://brandsweets.com/colors/brands/kraken-com), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono). — https://brandsweets.com/colors/midnightblue
- **Red** #ff0000 [pool] — Red is paired with #643cb4 in 4 real palettes, including Twitch's brand system and L'Oréal's brand system, as the accent. Seen in: Twitch (https://brandsweets.com/colors/brands/twitch-tv), L'Oréal (https://brandsweets.com/colors/brands/loreal-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), ElevenLabs (https://brandsweets.com/colors/brands/elevenlabs-io). — https://brandsweets.com/colors/red

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

- On white (#ffffff): 7.38:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.85:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8562cb (4.61:1); AA: background → #cccccc (4.59:1); AAA: text → #a388d7 (7.06:1); AAA: background → #fafafa (7.07:1)

## Brands using this color

- **Deno** — primary #6639ba (Δ 1.131) — https://brandsweets.com/colors/brands/deno-com
- **Deno** — accent #6639ba (Δ 1.131) — https://brandsweets.com/colors/brands/deno-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/643cb4-ae9cc4-dfc94e-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: "#643cb4" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.