Time Zone Converter

Convert times between any two time zones worldwide. See current time in popular cities and schedule across time zones instantly.

From Time Zone

To Time Zone

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UTC Offset Reference

Time Zone	UTC Offset	Region	DST?
UTC / GMT	+00:00	Universal	No
America/New_York (ET)	−05:00 / −04:00	US East	Yes
America/Chicago (CT)	−06:00 / −05:00	US Central	Yes
America/Denver (MT)	−07:00 / −06:00	US Mountain	Yes
America/Los_Angeles (PT)	−08:00 / −07:00	US West	Yes
Europe/London (GMT/BST)	+00:00 / +01:00	UK	Yes
Europe/Paris (CET)	+01:00 / +02:00	Central Europe	Yes
Asia/Dubai (GST)	+04:00	UAE	No
Asia/Kolkata (IST)	+05:30	India	No
Asia/Dhaka (BST)	+06:00	Bangladesh	No
Asia/Bangkok (ICT)	+07:00	SE Asia	No
Asia/Shanghai (CST)	+08:00	China	No
Asia/Tokyo (JST)	+09:00	Japan	No
Australia/Sydney (AEST)	+10:00 / +11:00	Australia East	Yes

Frequently Asked Questions

A time zone is a region of the globe that observes a uniform standard time for legal, commercial, and social purposes. There are 24 main time zones offset from UTC (Coordinated Universal Time) by whole or half hours. Some zones like India (UTC+5:30) and Nepal (UTC+5:45) use non-standard offsets.

Daylight Saving Time is the practice of advancing clocks by 1 hour in summer to extend evening daylight. Not all countries observe DST — most of Asia, Africa, and parts of South America do not. The US and EU observe DST, but transition on different dates, causing the offset between them to change briefly each year.

UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks and time. It does not observe DST and serves as the reference from which all other time zones are calculated. UTC replaced GMT (Greenwich Mean Time) as the world standard, though the two are practically equivalent for everyday use.

IANA (Internet Assigned Numbers Authority) time zone identifiers use the format Region/City (e.g., America/New_York, Asia/Tokyo). These are the standard used by operating systems, programming languages, and this tool. They automatically account for DST transitions, historical changes, and political boundary shifts.

There are 24 standard time zones based on whole-hour offsets from UTC (UTC−12 to UTC+12). However, the real total is higher when you include fractional-hour offsets. Countries like India (UTC+5:30), Iran (UTC+3:30), Afghanistan (UTC+4:30), and Nepal (UTC+5:45) use non-standard offsets, bringing the total number of distinct UTC offsets currently in use to around 38. The IANA time zone database tracks hundreds of named zones because political boundaries and historical changes create additional distinctions even within the same offset.

Daylight Saving Time (DST) advances clocks by one hour during summer months to extend evening daylight. The majority of the world does not observe DST. Countries that skip it include most of Asia (China, Japan, India, South Korea), nearly all of Africa, most of South America, and many island nations. Countries that do observe DST include the US, Canada, most of Europe, Australia, and New Zealand — though even within these regions some territories opt out (e.g., Arizona in the US). The EU voted to abolish DST but as of 2025 has not yet implemented the change uniformly.

The key principle is to always communicate a meeting time in UTC (or a clearly stated reference time zone) and let participants convert to their local time. Practical tips: convert the proposed time using this tool for each participant's zone; be aware of DST transitions which can shift overlaps unexpectedly; for recurring meetings, anchor to a fixed UTC time rather than a local time that shifts with DST. Typical "overlap windows" for global teams: New York / London overlap is 9 am–12 pm ET; London / India is 1 pm–5 pm GMT. Rotating meeting times fairly across time zones shows respect for all participants.

Most time zones are offset from UTC by a whole number of hours, but some countries use fractional offsets for geographic or political reasons. Notable examples: India (IST) = UTC+5:30, Iran = UTC+3:30, Afghanistan = UTC+4:30, Australia/Lord Howe = UTC+10:30. The most unusual is Nepal (NPT) = UTC+5:45 — the only major time zone with a 45-minute offset. These non-standard offsets exist so the country's standard time better aligns with solar noon across its territory.

IANA timezone identifiers (e.g., America/New_York) are unambiguous: they uniquely identify a time zone including its full history of DST rules and UTC offsets. Abbreviations like EST, IST, or CST are ambiguous — IST stands for Indian Standard Time, Irish Standard Time, and Israel Standard Time depending on context. EST is used by both the US Eastern Time (UTC−5) and Australian Eastern Standard Time (UTC+10). For software, APIs, and scheduling, always use IANA identifiers. Abbreviations are acceptable only in informal or UI-facing contexts where the region is already clear.

UTC (Coordinated Universal Time) is the global reference standard for timekeeping. It replaced GMT (Greenwich Mean Time) as the world's primary time standard in 1972 and is maintained by a network of atomic clocks. Unlike GMT — which is technically based on Earth's rotation and can vary by fractions of a second — UTC is kept in precise synchronisation using leap seconds added periodically to account for the gradual slowing of Earth's rotation. All other time zones are expressed as a positive or negative offset from UTC (e.g., UTC+5:30 for India, UTC−5:00 for US Eastern Standard Time). UTC never observes Daylight Saving Time, making it the stable foundation for international aviation, internet protocols, financial markets, and global software systems.

About This Timezone Converter

This free timezone converter converts a date and time from one IANA time zone to any other, accounting for daylight saving time transitions automatically. Select a source zone, enter a date and time, and choose a target zone to see the converted result.

The IANA Time Zone Database (tzdata) is the authoritative source used by all major operating systems and programming languages. This tool uses that database to handle DST rules and historical offsets correctly.

When to use this converter

Scheduling international meetings across multiple time zones
Debugging timestamps in server logs from different regions
Converting event times for a global audience

Standards & References

How It Works

Pick Time Zones

Select source and target time zones from the full IANA database. Popular zones are listed first for quick access.

Enter Date & Time

Enter the date and time to convert, or click "Use Current Time" to convert the current moment. DST is handled automatically.

See Converted Time

The converted time appears instantly with the UTC offset difference. The world clock shows current time in major cities.

Common Use Cases

International Meetings

Schedule video calls and online meetings across time zones so all participants know the correct local time without confusion.

Flight & Travel Planning

Convert departure and arrival times when booking international flights. Understand how many hours you cross and plan for jet lag.

Remote Work & Dev Teams

Coordinate with distributed teams and set up deployments or maintenance windows at the right local time for all regions.

Live Events & Broadcasts

Find out what time a live webinar, sports event, or TV broadcast starts in your local time zone from the announced UTC/ET/PT time.

Financial Markets

Track when stock markets open and close — NYSE opens at 09:30 ET, London at 08:00 GMT, Tokyo at 09:00 JST. Convert to your local time.

Family & Friends Abroad

Know the right time to call family or friends living in different countries without waking them up or missing the good time to reach them.

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