TimeandTool

Time Zone Converter

Convert a time between any two time zones.

Related Tools

World ClockMeeting Planner

Popular Time Zone Conversions

By Abbreviation

EST → PST3 hours behindEST → GMT5 hours aheadEST → IST10 hours 30 minutes aheadEST → CET6 hours aheadEST → JST14 hours aheadGMT → IST5 hours 30 minutes aheadGMT → JST9 hours aheadGMT → AEST11 hours aheadGMT → CST6 hours behindGMT → CST8 hours aheadIST → JST3 hours 30 minutes aheadIST → GMT5 hours 30 minutes behindIST → EST10 hours 30 minutes behindCET → EST6 hours behindCET → IST4 hours 30 minutes aheadCET → JST8 hours aheadPST → EST3 hours aheadPST → GMT8 hours aheadUTC → EST5 hours behindUTC → IST5 hours 30 minutes ahead

By City

New York → London5 hours aheadNew York → Tokyo14 hours aheadNew York → Dubai9 hours aheadNew York → Sydney16 hours aheadLondon → New York5 hours behindLondon → Tokyo9 hours aheadLondon → Dubai4 hours aheadLondon → Singapore8 hours aheadTokyo → New York14 hours behindTokyo → London9 hours behindDubai → London4 hours behindDubai → New York9 hours behindSydney → London11 hours behindSydney → Singapore3 hours behindToronto → London5 hours aheadParis → New York6 hours behindBerlin → New York6 hours behindMumbai → London5 hours 30 minutes behindSingapore → London8 hours behindLos Angeles → New York3 hours ahead

Timezone Quick Reference

AbbrFull NameUTC OffsetDST
GMTGreenwich Mean TimeUTC+0:00Yes
UTCCoordinated Universal TimeUTC+0:00No
ISTIndia Standard TimeUTC+5:30No
ESTEastern Standard TimeUTC-5:00Yes
PSTPacific Standard TimeUTC-8:00Yes
CSTCentral Standard TimeUTC-6:00Yes
MSTMountain Standard TimeUTC-7:00Yes
ASTAtlantic Standard TimeUTC-4:00Yes
NSTNewfoundland Standard TimeUTC-3:30Yes
BRTBrasília TimeUTC-3:00No
WETWestern European TimeUTC+0:00Yes
CETCentral European TimeUTC+1:00Yes
EETEastern European TimeUTC+2:00Yes
MSKMoscow Standard TimeUTC+3:00No
GSTGulf Standard TimeUTC+4:00No
PKTPakistan Standard TimeUTC+5:00No
BSTBangladesh Standard TimeUTC+6:00No
SGTSingapore TimeUTC+8:00No
HKTHong Kong TimeUTC+8:00No
CST (China)China Standard TimeUTC+8:00No
JSTJapan Standard TimeUTC+9:00No
KSTKorea Standard TimeUTC+9:00No
AESTAustralian Eastern Standard TimeUTC+11:00Yes
NZSTNew Zealand Standard TimeUTC+13:00Yes
CATCentral Africa TimeUTC+2:00No
EATEast Africa TimeUTC+3:00No
WATWest Africa TimeUTC+1:00No

UTC offsets shown for January 15, 2026 (winter reference). DST indicators reflect whether the offset changes between January and July.

Understanding Time Zones

UTC — the universal anchor. Coordinated Universal Time (UTC) is the basis for all civil time zones. Every time zone is defined as a fixed or seasonally varying offset from UTC. Aviation, GPS satellites, and internet infrastructure all operate on UTC, making it the common language of time across industries and borders. Unlike time zones with DST, UTC never changes — which is why it is the preferred reference for logging events, scheduling across regions, and database timestamps.

The IANA timezone database. Behind every accurate time conversion is the IANA Time Zone Database (also called tz database or zoneinfo), the authoritative global record of time zone rules. It documents every historical change, current DST schedule, and future planned adjustment for over 400 named time zones. TimeandTool uses the IANA database via the JavaScript Intl.DateTimeFormat API, so results reflect real-world DST transitions — including edge cases like the US spring-forward in March and the EU autumn clock-change in October.

Daylight saving time — what changes and what doesn't. Approximately 70 countries observe daylight saving time, typically shifting clocks forward by one hour in spring and back in autumn to extend evening daylight. However, the dates differ by hemisphere and country: the US and Canada change clocks on different Sundays than the European Union, and countries like Australia change in September (spring in the southern hemisphere). Many regions — including India, China, Japan, the UAE, and most of Africa — never change clocks, making them simpler anchors for international scheduling.

Why time zones matter for global business. A one-hour scheduling error caused by a DST transition or incorrect offset assumption can result in missed meetings, delayed deployments, or compliance failures. For remote teams spanning multiple continents, establishing a shared UTC-based schedule and always confirming times with full offset notation (e.g., “Monday 15:00 UTC”) eliminates ambiguity. Use our Meeting Planner to find business-hours overlap across up to six cities simultaneously.

Methodology: All UTC offsets and DST indicators on this page are computed using the Intl.DateTimeFormat API with the IANA timezone database built into the V8 JavaScript engine. The reference table uses January 15, 2026 as a fixed winter date to avoid DST ambiguity.

Frequently Asked Questions

Select your source time zone, enter the date and time, then select your destination time zone. The converter instantly shows the equivalent local time and UTC offset difference. You can also use our abbreviation shortcuts — for example, /timezone/converter/est/gmt — to jump straight to a specific pair.
Yes. The converter uses the IANA time zone database via the JavaScript Intl API, which includes complete historical and future DST rules for every time zone worldwide. When you select a specific date, results automatically reflect whether DST is in effect on that date.
UTC (Coordinated Universal Time) is the primary time standard used worldwide for civil timekeeping, aviation, and computing. All time zones are defined as offsets from UTC — for example, New York is UTC-5 in winter (EST) and UTC-4 in summer (EDT). UTC itself never observes daylight saving time, making it a stable reference for international scheduling.
EST (Eastern Standard Time) is UTC-5 and applies in winter months — typically from the first Sunday in November to the second Sunday in March. EDT (Eastern Daylight Time) is UTC-4 and applies in summer. 'Eastern Time' (ET) refers to whichever offset is currently active. Our converter automatically applies the correct offset for any date you choose.
GMT (Greenwich Mean Time) and UTC are often used interchangeably, but they differ slightly. UTC is based on atomic clocks and is the authoritative civil time standard, while GMT is a historical time zone based on solar time at the Royal Observatory in Greenwich. In practice, the two are within 0.9 seconds of each other and are treated as equivalent for everyday timekeeping.
Many regions near the equator and others with consistent sunlight year-round do not observe DST. These include India (IST, UTC+5:30), China (CST, UTC+8), Japan (JST, UTC+9), the UAE (GST, UTC+4), Singapore (SGT, UTC+8), and most of Africa. Their UTC offsets remain constant year-round, making scheduling to and from these zones more predictable.
IST most commonly refers to India Standard Time (UTC+5:30), used across all of India and Sri Lanka. It is notable for its non-standard 30-minute offset. IST can also stand for Irish Standard Time (UTC+1, used in summer in Ireland) or Israel Standard Time (UTC+2). Our converter uses India Standard Time as the default for IST.
Your browser automatically detects your local time zone. When you open the converter, 'My Time Zone' is pre-selected using the IANA identifier reported by your device (for example, America/New_York or Europe/London). You can also check your system settings — on Windows, look in Date & Time settings; on macOS, look in System Settings → General → Language & Region.
The IANA Time Zone Database (also called tz database or zoneinfo) is the authoritative reference for all world time zones. It is maintained by the Internet Assigned Numbers Authority and records every historical, current, and scheduled time zone change, including DST rules. Browsers, operating systems, and programming languages all rely on it — which is why our converter gives consistent results across platforms.
Use our Meeting Planner to find overlapping business hours across multiple cities. As a general rule: agree on a shared reference (usually UTC or the time zone of the person who calls the meeting), always confirm times in full format including date and UTC offset (e.g., 'Thursday 14:00 UTC'), and be aware of DST changes that can shift offsets by one hour on different dates in different countries.
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