What does UTC offset mean?

UTC offset is hours ahead of or behind Coordinated Universal Time. India is UTC+5:30 (5.5 hours ahead). New York is UTC-5 in winter or UTC-4 in summer.

What is the difference between GMT and UTC?

GMT and UTC are nearly identical and often used interchangeably. UTC is the scientific standard maintained by atomic clocks; GMT is a historical standard.

How does Daylight Saving Time affect conversions?

DST shifts clocks +1 hour in spring and −1 hour in autumn for observing countries, changing their UTC offset and the difference with non-observing countries.

What time zone is India in?

India uses Indian Standard Time (IST) = UTC+5:30, year-round (no DST).

What is the time difference between London and New York?

London is UTC+0 in winter (GMT) or UTC+1 in summer (BST). New York is UTC-5 in winter or UTC-4 in summer. The difference is usually 5 hours, though it can be 4 hours for a few weeks in spring and autumn when the US and UK change clocks on different dates.

Time Zone Converter, Convert Time Between World Cities

Quick Answer

To convert between time zones, find the UTC offset of each zone and subtract: Target Time = Source Time + (Target UTC offset − Source UTC offset). For example, from UTC+1 (Paris) to UTC−5 (US Eastern) in winter: subtract 6 hours.

What Is Time Zone Converter?

A timezone converter tells you what time it is in another city right now, or converts a specific time between zones, essential for scheduling international meetings and calls.

Time zones are defined by their offset from UTC (Coordinated Universal Time), ranging from UTC−12 to UTC+14. Many countries observe Daylight Saving Time (DST), shifting clocks by 1 hour in summer, meaning the offset between two locations can change twice a year.

This tool shows the current local time in all major time zones in real time, making it easy to find a window that works across regions, for example, business hours overlapping between London and New York.

How to Use

1The converter displays current time across all major time zones in real time.
2Use it to find what time it is in any city, or check if a given time in one zone corresponds to a reasonable hour in another.

Formula

Conversion

Target Time = Source Time + (Target UTC offset − Source UTC offset)

Cross-day rule

If result < 0 hours: subtract 1 day. If result ≥ 24 hours: add 1 day.

Example: 3:00 PM in New York (UTC−5, winter) → London (UTC+0)

Offset diff = 0 − (−5) = +5 hours
London time = 15:00 + 5 = 20:00

3:00 PM New York = 8:00 PM London in winter. The gap stays 5 hours in summer too, apart from a few weeks in spring and autumn when the US and UK change their clocks on different dates.

Tips & Things to Know

DST changes offset by ±1 hour for US, Canada, most of Europe, and Australia. China, Japan, India and the UAE do not observe DST.
US alone has 6 time zones: ET (New York), CT (Chicago), MT (Denver), PT (Los Angeles), AK, HI.
Countries that do not use DST, such as India (UTC+5:30) and the UAE (UTC+4), keep a fixed offset all year, so their time difference with DST countries changes twice a year.
For scheduling international meetings: look for the 9 AM–5 PM overlap between zones. New York (UTC−5) to London (UTC+0) in winter, a 9 AM–12 PM New York call lands at 2–5 PM in London, comfortable for both sides.
China spans five geographic time zones but uses a single UTC+8 standard, meaning sunrise arrives as late as 10 AM in western Xinjiang. Not all countries choose the geographically 'correct' offset.
IST (India) is UTC+5:30 and Nepal is UTC+5:45, half and three-quarter hour offsets that exist because the zones were calibrated to place solar noon as close as possible to 12:00 PM at the country's centre.

Time Zone Converter