# 🌍 Timezone & Intl Detector Detect your browser's timezone, locale, and internationalization settings. Understand how timezone reveals your location and the privacy implications of Intl APIs. Loading... Timezone Loading... UTC Offset Loading... Locale 0 Languages 00:00:00 Loading... Loading timezone... #### Privacy Warning: Timezone = Location **Your timezone reveals your approximate location** with ~15-minute precision. Combined with other fingerprinting data, it can identify your city or region. VPN users should ensure their timezone matches their VPN location to avoid detection. ### Timezone Details Timezone (IANA) Loading... UTC Offset Loading... Timezone Abbreviation Loading... DST Active Loading... Date.getTimezoneOffset() Loading... Estimated Location Loading... Worker Consistency Checking... ### Locale & Language Settings Primary Locale Loading... Language Loading... Country/Region Loading... All Languages Loading... ### Intl Formatting Examples Date (Long) Loading... Time (Medium) Loading... Number (Decimal) Loading... Currency (USD) Loading... Relative Time Loading... List Format Loading... **Timezone fingerprinting** uses your browser's timezone and locale settings to estimate your geographic location and create a unique identifier: ##### How Timezone Reveals Location - **IANA Timezone** - "America/New\_York" reveals you're in Eastern Time - **UTC Offset** - UTC-5:00 narrows down to specific time zones - **DST Detection** - Daylight Saving Time patterns reveal country/region - **Offset Changes** - Timezone offset changes reveal when DST starts/ends ##### Privacy Implications Your timezone is one of the most revealing pieces of fingerprinting data because: - It's **extremely stable** - users rarely change their timezone - It's **precise** - narrows location to ~15-minute longitude slice - It's **easy to detect** - exposed via JavaScript Date API - It **reveals VPN misconfigurations** - timezone doesn't match VPN location ``` // Detect user timezone const timezone = Intl.DateTimeFormat().resolvedOptions().timeZone; console.log('Timezone:', timezone); // "America/Los_Angeles" // Get UTC offset (in minutes) const offset = new Date().getTimezoneOffset(); console.log('UTC offset:', -offset / 60); // -8 (PST) // Detect DST const jan = new Date(2024, 0, 1).getTimezoneOffset(); const jul = new Date(2024, 6, 1).getTimezoneOffset(); const isDST = Math.max(jan, jul) !== new Date().getTimezoneOffset(); console.log('DST active:', isDST); ``` The **Intl (Internationalization) API** provides locale-specific formatting that reveals cultural and regional preferences: ##### Locale Detection ``` // Get user locale const locale = Intl.DateTimeFormat().resolvedOptions().locale; console.log('Locale:', locale); // "en-US", "fr-FR", "ja-JP" // Get all preferred languages const languages = navigator.languages; console.log('Languages:', languages); // ["en-US", "en", "es"] ``` ##### Formatting Reveals Culture How you format dates, numbers, and currency reveals your region: - **Date Format** - US: "12/31/2024" (MM/DD/YYYY) - EU: "31/12/2024" (DD/MM/YYYY) - ISO: "2024-12-31" (YYYY-MM-DD) - **Number Format** - US/UK: "1,234.56" (comma thousands, period decimal) - EU: "1.234,56" (period thousands, comma decimal) - India: "1,23,456.78" (lakh system) - **Currency** - US: "$1,234.56" - EU: "1 234,56 €" - Japan: "¥1,234" ``` // Format examples revealing culture const num = 1234567.89; // US formatting new Intl.NumberFormat('en-US').format(num); // "1,234,567.89" // German formatting new Intl.NumberFormat('de-DE').format(num); // "1.234.567,89" // Currency formatting new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' }).format(123.45); // "$123.45" ``` If you're using a VPN or want to hide your location, you must spoof your timezone: ##### 1. Browser Extension (Easiest) Use extensions like "Timezone Shifter" or "Chameleon" to override timezone. ##### 2. JavaScript Spoofing (Automation) ``` // Spoof Intl.DateTimeFormat const originalDateTimeFormat = Intl.DateTimeFormat; Intl.DateTimeFormat = function(locales, options) { // Force specific timezone const opts = { ...options, timeZone: 'America/New_York' }; return new originalDateTimeFormat(locales, opts); }; // Spoof Date.getTimezoneOffset const originalGetTimezoneOffset = Date.prototype.getTimezoneOffset; Date.prototype.getTimezoneOffset = function() { // Return offset for New York (UTC-5 or UTC-4) return 300; // 300 minutes = UTC-5 }; ``` ##### 3. Browser Launch Arguments (Puppeteer/Playwright) ``` // Puppeteer example const browser = await puppeteer.launch({ args: ['--timezone=America/New_York'] }); // Playwright example const browser = await chromium.launch({ env: { TZ: 'America/New_York' } }); ``` ##### 4. Use Scrapfly API (Recommended) **Scrapfly** automatically handles timezone spoofing to match your proxy location: ``` from scrapfly import ScrapflyClient, ScrapeConfig client = ScrapflyClient(key='YOUR_KEY') result = client.scrape(ScrapeConfig( url='https://example.com', country='US', # Scrapfly auto-sets timezone to match US location asp=True, render_js=True )) ``` Complete code to detect and analyze timezone in your applications: ``` // Get comprehensive timezone information function getTimezoneInfo() { const date = new Date(); const dtf = Intl.DateTimeFormat(); const resolved = dtf.resolvedOptions(); // Detect DST const jan = new Date(date.getFullYear(), 0, 1).getTimezoneOffset(); const jul = new Date(date.getFullYear(), 6, 1).getTimezoneOffset(); const isDST = Math.max(jan, jul) !== date.getTimezoneOffset(); return { // IANA timezone timezone: resolved.timeZone, // "America/New_York" // UTC offset offsetMinutes: -date.getTimezoneOffset(), offsetHours: -date.getTimezoneOffset() / 60, offsetString: formatOffset(-date.getTimezoneOffset()), // Locale info locale: resolved.locale, language: navigator.language, languages: navigator.languages, // DST info isDST: isDST, // Formatting dateFormat: dtf.format(date), timeFormat: new Intl.DateTimeFormat(resolved.locale, { hour: 'numeric', minute: 'numeric', second: 'numeric' }).format(date) }; } function formatOffset(minutes) { const hours = Math.floor(Math.abs(minutes) / 60); const mins = Math.abs(minutes) % 60; const sign = minutes >= 0 ? '+' : '-'; return `UTC${sign}${hours}:${mins.toString().padStart(2, '0')}`; } // Usage const tzInfo = getTimezoneInfo(); console.log('Timezone Info:', tzInfo); ```