# #643cd3

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

## Values

- Hex: `#643cd3`
- RGB: rgb(100, 60, 211)
- HSL: hsl(256, 63%, 53%)
- OKLCH: oklch(0.498 0.216 288)
- Relative luminance: 0.1064
- Nearest named color: Blurple (#5539cc, Δ 2.925) — https://brandsweets.com/colors/blurple
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/643cd3

## Tints & shades

- Tints (toward white): #7450d7, #8261db, #9276e0, #9f86e4, #b09be8, #bdacec, #cec1f1, #dbd1f5, #ebe6f9, #f8f7fd
- Shades (toward black): #562dc8, #4d29b3, #44249e, #3b1f89, #341b79, #2b1764, #22124f, #190d3a, #100825, #070411

## Harmonies

- Complementary: #aad33c
- Analogous: #3c5fd3, #af3cd3
- Triadic: #d3643c, #3cd364
- Split-complementary: #d3af3c, #5fd33c
- Tetradic: #d33c5f, #aad33c, #3cd3af

## Colors that go with #643cd3

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 #643cd3: softer than #000 and cool enough to feel like part of the same palette. Seen in: UEFA (https://brandsweets.com/colors/brands/uefa-com), Campus (https://brandsweets.com/palettes/friendly#campus), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #643cd3's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Yahoo (https://brandsweets.com/colors/brands/yahoo-com), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com), Guinness (https://brandsweets.com/colors/brands/guinness-com), Walmart (https://brandsweets.com/colors/brands/walmart-com). — https://brandsweets.com/colors/royalblue
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #643cd3: 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
- **Amber** #ffbf00 [pool] — Amber is paired with #643cd3 in 5 real palettes, including Warner Bros.'s brand system and Walmart's brand system, as the accent. Seen in: Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), Walmart (https://brandsweets.com/colors/brands/walmart-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 4 real palettes, including Zillow's brand system and Signal's brand system put Blue beside #643cd3, as the lead colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), Signal (https://brandsweets.com/colors/brands/signal-org), Pixar (https://brandsweets.com/colors/brands/pixar-com), Headspace (https://brandsweets.com/colors/brands/headspace-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #643cd3: 6 real palettes, including Zillow's brand system and Warbyparker's brand system, as the supporting colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Oreo (https://brandsweets.com/colors/brands/oreo-com), Unilever (https://brandsweets.com/colors/brands/unilever-com). — https://brandsweets.com/colors/cobalt
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #643cd3: 7 real palettes, including Coca-Cola's brand system and Qualcomm's brand system, as the supporting colour. Seen in: Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social), Roblox (https://brandsweets.com/colors/brands/roblox-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #643cd3 in 9 real palettes, including Gemstone and Wells Fargo's brand system, as the accent. Seen in: Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Netflix (https://brandsweets.com/colors/brands/netflix), Ulta Beauty (https://brandsweets.com/colors/brands/ulta-com). — https://brandsweets.com/colors/crimson

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

- On white (#ffffff): 6.71:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #6137d2 (7.03:1)
- On black (#000000): 3.13:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #8261db (4.68:1); AA: background → #d4d4d4 (4.53:1); AAA: text → #9f86e4 (7:1)

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- 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/643cd3-ab9cc4-dfbf4e-291f2d-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: "#643cd3" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.