🌐 Time Zone Converter
Convert time between any two time zones. Plan meetings across time zones. Free, instant, no signup.
Add time zones to see overlapping business hours (9 AM–5 PM) highlighted in green.
💡 Click a time zone's ✕ to remove it. Your selection is saved in your browser.
📋 When to Use the Time Zone Converter
- Schedule international meetings — Find a time that works across multiple time zones without mental math. The Meeting Planner shows you at a glance when everyone's business hours overlap.
- Plan travel itineraries — Convert departure and arrival times between time zones so you never miss a flight or connection.
- Coordinate with remote teams — Whether your team spans San Francisco, Berlin, and Bangalore, see exact local times and plan standups, reviews, and deadlines.
- Follow global events live — Convert event start times from the organizer's time zone to your own — product launches, sports events, conference keynotes.
- Stay in touch with family abroad — Check the local time for loved ones in different countries so you call at a reasonable hour.
⚙️ How the Time Zone Converter Works
The Time Zone Converter uses your browser's built-in Intl.DateTimeFormat and Intl.supportedValuesOf('timeZone') APIs to compute accurate time conversions for any IANA time zone. No external APIs are called — all computation happens locally in your browser, making it privacy-first and offline-capable.
When you select a source time zone, enter a date and time, and choose a target time zone, the tool creates a Date object in the source zone, then formats it using the target zone's locale settings. The result shows the converted time, the date (with "next day" / "previous day" indicators when crossing midnight), and the UTC offset difference. In Meeting Planner mode, each added time zone is rendered on a 24-hour timeline. Business hours (9 AM–5 PM local time) are highlighted in green. The tool calculates the intersection of all business-hour ranges and displays the overlap window at the top.
How to Use the Time Zone Converter
- Select a source time zone — From the "From" dropdown, choose the time zone you want to convert from. All IANA time zones are available, categorized by region.
- Set the date and time — Pick the date and time you want to convert using the date and time inputs. Defaults to the current date and time.
- Select a target time zone — Choose the "To" time zone. The converted time, date, UTC offsets, and a human-readable note (e.g., "next day" / "previous day") appear instantly.
- Switch to Meeting Planner — Click the "Meeting Planner" tab. Add time zones using the dropdown and "+ Add" button. The timeline shows local hours for each zone — business hours are green. The overlap window at the top shows when all zones' business hours intersect.
Frequently Asked Questions
How accurate is the time zone converter?
The Time Zone Converter uses your browser's IANA timezone database — the same database used by operating systems worldwide. Times are accurate to the second and automatically account for daylight saving time (DST) transitions. No external server calls are needed.
How many time zones can I compare in Meeting Planner?
You can add as many time zones as you like. Each zone appears as a row on the 24-hour timeline. The overlap calculator finds the intersection of business hours across all added zones. Performance remains smooth even with 20+ zones.
What does "next day" / "previous day" mean in the result?
When the converted time falls on a different calendar date from the source time, the tool shows "(next day)" or "(previous day)" to prevent confusion. For example, 8 PM EST converts to 1 PM NZST the next day.
Does the converter handle daylight saving time?
Yes. All IANA time zones include complete DST rules. When a time zone enters or exits DST, the UTC offset and converted times update automatically. You don't need to adjust anything manually.
Is my data sent to a server when I use this tool?
No. All time zone conversion and meeting planning happens entirely in your browser using the built-in Intl APIs. Your data never leaves your device. No information is stored, tracked, or transmitted.
Does the tool work offline?
Yes. Once the page loads, all computation runs client-side. No internet connection is needed for conversions. Your meeting planner selections are saved in localStorage and persist across sessions.
What IANA time zones are included?
The tool uses Intl.supportedValuesOf('timeZone'), which returns all IANA time zones supported by your browser. This includes all major time zones across every continent — over 500 zones — from UTC to the Pacific Islands.