🌐 Time Zone Calculator

Convert a date and time from one UTC offset to another using fixed offset arithmetic.

Convert Time

Your Result

Converted Time
Source Time
Time Difference

This calculator uses fixed UTC offset arithmetic and does not automatically apply Daylight Saving Time. Choose the offset that is currently in effect (e.g., -4 for EDT, -5 for EST) for accurate results.

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How the Time Zone Calculator Works

Every time zone is defined by an offset from Coordinated Universal Time (UTC). To convert a time from one zone to another, the calculator first converts the source time to UTC, then applies the target zone's offset.

Formula

UTC Time = Source Local Time − Source UTC Offset
Target Local Time = UTC Time + Target UTC Offset

A Note on Daylight Saving Time

Because this tool uses fixed UTC offsets rather than a full time zone database, it does not automatically adjust for Daylight Saving Time (DST). Be sure to select the offset that reflects the current DST status of each location (for example, US Eastern Time is UTC-5 in winter and UTC-4 during DST).

Frequently Asked Questions

Does this calculator account for Daylight Saving Time?

No. It performs fixed offset arithmetic, so you must manually select the correct offset for the current season (e.g., EST vs. EDT) in each location.

What is UTC?

UTC (Coordinated Universal Time) is the primary time standard used worldwide. All time zones are expressed as a positive or negative offset from UTC.

How do I find my UTC offset?

Search "[your city] UTC offset" or check your device's time zone settings, which typically display the current offset such as UTC-5 or UTC+1.

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