Time Zone Converter

About this tool

This time-zone converter turns a date and time in one selected IANA zone into formatted times for UTC, Kathmandu, Kolkata, London, Berlin, New York, Los Angeles, Tokyo, and Sydney. It uses the browser's internationalization time-zone data, so daylight-saving offsets are applied for the selected date instead of assuming one fixed offset. Non-whole-hour offsets such as Kathmandu (+05:45) and Kolkata (+05:30) are included. The tool displays converted times but does not detect every ambiguous or nonexistent local clock time during a daylight-saving transition; verify unusual transition cases with the source zone's official rules.

Why use it

• Live Multi-city Clocks: Add multiple cities and compare their current times side-by-side. Useful for remote teams in different continents who need a persistent reference rather than a one-off conversion.

• Automatic DST Handling: DST transitions are applied based on the actual date entered, not a fixed offset. A date before the spring-forward in the US uses EST; after the transition it uses EDT. No manual adjustment needed.

• Meeting Slot Finder: Enter a proposed meeting time and see what it corresponds to in every participant's location simultaneously. Identify a slot that falls within business hours for all parties without spreadsheet gymnastics.

• UTC Offset Display: Each result shows the UTC offset in effect — IST +5:30, EST −5:00, CET +1:00 — so participants in any location can verify the conversion independently using any timezone reference.

• ISO 8601 Copy Format: One-click copy produces a datetime string with the UTC offset in ISO 8601 format, such as 2026-05-15T10:00:00−08:00. Paste directly into calendar apps, APIs, or scheduling tools for unambiguous timezone-aware timestamps.

• Complete Privacy: Your local device time is read on-device. No query times, cities, or meeting schedules are sent to any server or stored in any database.

How to use

1. Select the source city or time zone from the searchable dropdown or type a city name
2. Enter the date and time you want to convert — use 24-hour format to avoid AM/PM ambiguity
3. Add one or more target cities using the Add City button
4. Read the converted time for each target city alongside its UTC offset and DST status
5. Toggle to the DST visual to see when spring-forward and fall-back transitions occur near your chosen date
6. Copy the ISO 8601 formatted time with offset for pasting into calendar invitations or meeting schedulers

When it helps

• When scheduling a video call with international colleagues and you need to find a time that falls within business hours across three or more continents
• When booking a flight or train and the departure and arrival times are listed in local time for two different cities
• When a webinar, product launch, or live event is announced in Pacific Time and you need to know when to set your alarm
• When a client in a different country sends you a deadline expressed in their local time and you need to know the equivalent in your own time zone
• When checking whether a DST transition falls near a critical meeting date and you need to confirm the offset does not shift mid-event
• When writing a meeting invitation and you want to include the correct UTC offset so participants everywhere can verify the time independently

Examples

Tips

• Always include the UTC offset when sending a meeting invite — most calendar apps convert it correctly, but the written offset lets recipients verify manually if they suspect a DST error
• Avoid scheduling meetings near 02:00 on the last Sunday in March (EU) or second Sunday in March (US) — these are DST transition hours that can cause a one-hour confusion
• India (IST +5:30), Iran (IRST +3:30), and Newfoundland (NST −3:30) all use half-hour offsets — make sure your tool accounts for these rather than rounding to the nearest whole hour
• Use 24-hour time format in written communications to avoid AM/PM ambiguity — 14:00 is unambiguous; 2:00 PM is not in every locale
• Pin your most-used city combination — your home zone plus your team's main hub — so you always have a live reference visible without re-entering it

Frequently Asked Questions

Glossary

UTC (Coordinated Universal Time)

The primary international time standard against which all time zones are defined as offsets. UTC is maintained by atomic clocks and does not observe daylight saving time. It replaced GMT as the technical standard but the two are practically equivalent for everyday use.

Time Zone Offset

The difference, in hours and minutes, between a location's local time and UTC. For example, IST (India Standard Time) is UTC+5:30, meaning local time is 5 hours and 30 minutes ahead of UTC.

Daylight Saving Time (DST)

A seasonal practice of advancing clocks by one hour in spring to extend evening daylight and returning to standard time in autumn. Not all countries observe DST; transitions occur on different dates in different regions.

IANA Time Zone

A standardised time zone identifier in the format Region/City (e.g., America/New_York, Asia/Tokyo) maintained by the Internet Assigned Numbers Authority. IANA identifiers encode historical and current DST rules for every zone.

ISO 8601

An international standard for representing dates and times as text strings. A timezone-aware ISO 8601 timestamp includes the UTC offset, for example 2026-05-15T14:30:00+05:30. This format is unambiguous and machine-readable.

Solar vs Civil Time

Solar time is based on the sun's position and varies continuously with longitude. Civil time is the standardised legal time adopted by governments within a zone. Civil time zones are typically one-hour-wide bands, though political and practical factors cause some zones to deviate.