Timezone Converter

A timezone converter translates local times across world time zones (UTC/GMT, Eastern, Pacific, Central European, India, Japan), accounting for daylight saving time (DST) shifts. It enables remote workers, international businesses, and travelers to schedule cross-border meetings without scheduling errors.

Interactive Timezone ConverterInstant In-Browser Calculation

Estimated Output

Formula and Calculation Method

Universal Time Coordinated (UTC) Conversion:

UTC Time = Local Time - Local UTC Offset
Target City Time = UTC Time + Target City UTC Offset

Standard Global UTC Offsets: New York / EST (UTC-5 / EDT UTC-4), London / GMT (UTC+0 / BST UTC+1), Paris / CET (UTC+1 / CEST UTC+2), India / IST (UTC+5:30), Tokyo / JST (UTC+9), Sydney / AEST (UTC+10 / AEDT UTC+11).

Worked Example and Step-by-Step Calculation

Scheduling an International Call: 10:00 AM New York (EDT, UTC-4)

Input Values:

Origin Time: 10:00 AM New York (EDT, UTC-4)
Target Cities: London (BST, UTC+1), New Delhi (IST, UTC+5:30), Tokyo (JST, UTC+9)

1. Convert to UTC: 10:00 AM EDT + 4 hrs = 14:00 UTC (2:00 PM UTC)

2. London (UTC+1): 14:00 + 1 hr = 3:00 PM (15:00 BST)

3. New Delhi (UTC+5:30): 14:00 + 5.5 hrs = 7:30 PM (19:30 IST)

4. Tokyo (UTC+9): 14:00 + 9 hrs = 11:00 PM (23:00 JST)

Result: 10:00 AM NYC = 3:00 PM London = 7:30 PM New Delhi = 11:00 PM Tokyo

How to Use the Timezone Converter

Select your origin city or time zone.
Pick the date and time you want to convert.
Add target comparison cities (e.g. London, San Francisco, Singapore, Sydney).
Drag the interactive 24-hour time slider to see overlapping business hours across all selected locations.

Common Mistakes, Limitations & Practical Guidance

Daylight Saving Time (DST) changeover dates differ between the US (second Sunday in March) and Europe (last Sunday in March), creating 1 to 3 week temporary offset anomalies.
Certain regions (e.g. India, Nepal, parts of Australia) use half-hour or 45-minute non-standard UTC offsets.

Frequently Asked Questions About Timezone Converter

What is UTC and how does it relate to GMT?

UTC (Coordinated Universal Time) is the global scientific atomic time standard. GMT (Greenwich Mean Time) is a historic solar time zone sharing the exact same current clock time as UTC (UTC+0).

Why do time differences change during March and October/November?

Different countries start and end Daylight Saving Time on different weekends. The US changes clocks in early March, while the UK and European Union change in late March, temporarily altering time differences between New York and London by one hour for several weeks.

Which countries do not observe Daylight Saving Time?

Over 60% of the world does not observe DST, including all of Japan, China, India, Singapore, most of Africa, and U.S. jurisdictions including Arizona (except Navajo Nation) and Hawaii.

What is the International Date Line?

The International Date Line roughly follows the 180° meridian in the Pacific Ocean. Crossing it westward advances the calendar date by one full day; crossing it eastward moves the date back by one day.

How does this tool connect to Time and Date Calculator?

While this tool focuses on multi-city world clock comparisons and meeting planning, our Time and Date Calculator handles age calculations and calendar day intervals.