ZoneShift: Easy Timezone Changer

Change the timezone your browser reports to websites. One dropdown, one switch. DST-correct, no history access.

ZoneShift is a lightweight developer tool designed to accurately spoof your browser's client-side timezone. It allows QA testers, developers, and privacy-conscious users to simulate global timezones without altering their system clock. Key Features: Deep API Patching: Overrides the core JavaScript Date object and modern Intl.DateTimeFormat APIs. Iframe Support: Successfully injects into dynamic iframes (including about:blank and srcdoc). DST-Aware: Respects historical daylight saving time transitions (validated against 1.6+ million date combinations). Input Sync: Works seamlessly with native HTML <input type="date"> elements and complex calendar grids. Zero Bloat: No tracking, no ads, no analytics. Requires only the storage permission to save your selected timezone. Important Limitation / Disclaimer: ZoneShift strictly modifies the client-side JavaScript timezone. It is NOT a VPN and does not mask your IP address. Websites that calculate time server-side based on your IP (e.g., time.is) will still detect your real location. ZoneShift is built specifically for local UI/UX testing and client-side anti-fingerprinting. How to use: Open the extension popup. Search and select a timezone. Toggle the override to active. The current tab reloads automatically to apply the clean state.