Universal Time Coordinated. It is the core time standard used to keep all world clocks in synchronization.

Daylight Saving Time. Many countries advance their clocks by one hour during warmer months to extend evening daylight.

CALCULATOR

Time Zone Calculator

Time Zone Converter

Source Date & Time

Source Time Zone

Target Time Zone

Quick Search

Source Offset

Target Offset

Time Difference

Source Time (UTC)

Target Time (Kolkata)

United States Time Zones

Eastern Time (ET)

America/New_York

Standard:UTC-05:00

DST:UTC-04:00

Central Time (CT)

America/Chicago

Standard:UTC-06:00

DST:UTC-05:00

Mountain Time (MT)

America/Denver

Standard:UTC-07:00

DST:UTC-06:00

Pacific Time (PT)

America/Los_Angeles

Standard:UTC-08:00

DST:UTC-07:00

Alaska Time

America/Anchorage

Standard:UTC-09:00

DST:UTC-08:00

Hawaii-Aleutian

Pacific/Honolulu

Standard:UTC-10:00

Atlantic Time

America/Puerto_Rico

Standard:UTC-04:00

Samoa Time

Pacific/Pago_Pago

Standard:UTC-11:00

Chamorro Time

Pacific/Guam

Standard:UTC+10:00

World Time Zone Map

UTC-12

UTC-11

UTC-10

UTC-9

UTC-8

UTC-7

UTC-6

UTC-5

UTC-4

UTC-3

UTC-2

UTC-1

UTC+0

UTC+1

UTC+2

UTC+3

UTC+4

UTC+5

UTC+6

UTC+7

UTC+8

UTC+9

UTC+10

UTC+11

Simplified time zone map - each block represents 15° longitude (1 hour)

A time zone is a region on Earth that uses a uniform time. They are often based on the boundaries of countries or lines of longitude. Generally, a time change of 1 hour is required with each 15° change of longitude.

UTC Offset Range

From UTC-12:00 to UTC+14:00

Most offsets are whole hours, but some are half-hour (UTC+05:30) or quarter-hour (UTC+12:45)

Interesting Facts

China uses single time zone despite spanning 5 zones
Russia has 11 time zones
Nepal uses UTC+5:45 (quarter-hour offset)

Daylight Saving Time (DST)

Spring Forward

Clocks advance 1 hour

In early spring, clocks are set forward 1 hour to extend evening daylight. This typically happens in March for most of US and Europe.

Fall Back

Clocks return 1 hour

In autumn, clocks are set back 1 hour to standard time. This typically happens in November for US and October for Europe.

DST Observance

Not all regions observe DST. Countries near the equator and some regions in Asia and Africa do not change their clocks. Arizona (US) and Hawaii also do not observe DST.

UTC (Coordinated Universal Time)

What is UTC?

UTC is the primary time standard by which the world regulates clocks and time. It is based on highly precise atomic clocks and the Earth's rotation.

UTC vs GMTUTC is a standard, GMT is a time zone

UTC Offset RangeUTC-12:00 to UTC+14:00

DST ImpactUTC doesn't observe DST

Current UTC Time

14:23:40

Saturday, March 21, 2026

World Clock - Current Times

🇬🇧 London

02:23 PM

Sat

🇺🇸 New York

10:23 AM

Sat

🇯🇵 Tokyo

11:23 PM

Sat

🇦🇺 Sydney

01:23 AM

Sun

🇦🇪 Dubai

06:23 PM

Sat

🇫🇷 Paris

03:23 PM

Sat

🇸🇬 Singapore

10:23 PM

Sat

🇷🇺 Moscow

05:23 PM

Sat

Time Zone Calculator: Sync Your World Across Borders

In our hyper-connected global economy, we are constantly communicating across borders. Knowing the exact time in London, Tokyo, or New York isn't just a curiosity—it's a requirement for business meetings, international travel, and keeping in touch with loved ones. Our Time Zone Calculator is an intelligent converter that helps you bridge the gap between different locales instantly.

Calculating timezone differences is notoriously difficult due to Daylight Saving Time (DST) changes, which happen on different dates in different countries. A city might be 5 hours ahead of you in June and 6 hours ahead in November. our calculator uses a real-time global database to account for these shifts, ensuring you never miss a call or arrive late for a flight.

In this guide, we'll explain how timezones are structured based on UTC, discuss the history of Daylight Saving Time, and offer tips on how to plan international conference calls without waking anyone up in the middle of the night.

How Global Timezones Work

The world is divided into 24 main longitudinal slices, each representing one hour of the Earth's 24-hour rotation. The reference point for all of these is **UTC (Coordinated Universal Time)**, located at the Royal Observatory in Greenwich, London (Prime Meridian).

Most timezones are expressed as an offset from UTC (e.g., IST is UTC+5:30). However, geopolitical boundaries mean that some timezones are oddly shaped, and some regions (like India or Nepal) use half-hour or 45-minute offsets.

The biggest source of confusion is Daylight Saving Time. Many countries in the Northern and Southern hemispheres 'spring forward' or 'fall back' to maximize daylight, but since they do this on different calendar days, the offset between two cities can change multiple times a year.

How to Use the Online Time Zone Converter

Step 1: Select Your Base City: Choose the city or timezone you are currently in.
Step 2: Select Target City: Choose the destination or the city where your contact is located.
Step 3: Choose a Date/Time: If you are planning for the future, pick the specific date to account for DST changes.
Step 4: Interpret the Result: The tool will show the current time in both locations and the exact number of hours difference.
Step 5: Meeting Planner: Check the 24-hour slider to find a window where both cities are within 'working hours'.

Major City Time Offsets (Reference)

City	Standard Offset (UTC)	Daylight Saving (DST)	Key Industry
New York	-5:00 (EST)	-4:00 (EDT)	Finance / Media
London	+0:00 (GMT)	+1:00 (BST)	European Hub
Mumbai	+5:30 (IST)	No DST	IT / Tech Services
Tokyo	+9:00 (JST)	No DST	Electronics / Auto
Sydney	+10:00 (AEST)	+11:00 (AEDT)	Mining / Banking

Benefits of Our Time Zone Tool

✓
Always Up-to-Date
Uses the IANA Time Zone Database, the same source used by Apple, Google, and Microsoft.
✓
Visual Scheduler
Easily see when the overlap of 'Office Hours' occurs between any two points on Earth.
✓
Handles Odd Offsets
Correctly manages non-integer timezones like India (+5:30) and Nepal (+5:45).