Time Zone Converter
Convert a time between two time zones using UTC offsets, with the day shift shown.
Inputs
Formula
- Target time = source time − source offset + target offset
Every zone is defined by its offset from UTC. Convert to UTC first, then out again. Remember that daylight saving changes the offset for part of the year in many countries — use the offset in force on the date you care about.
Step-by-step calculation
- 1
To UTC
time − source offset
9
- 2
To target
+ target offset
04:00
Frequently asked questions
What does the Time Zone Converter do?
Convert a time between two time zones using UTC offsets, with the day shift shown. The Time Zone Converter on OneCalcApp returns the result instantly as you type, together with the formula and the substituted values.
How do I use the Time Zone Converter?
Enter your values in the input fields, choose the relevant units or options, and the Time Zone Converter recalculates automatically. You can copy, print or export the result.
Is the Time Zone Converter free to use?
Yes. The Time Zone Converter is completely free, needs no sign-up and has no usage limit on OneCalcApp.
How accurate is the Time Zone Converter?
It uses the standard formula Target time = source time − source offset + target offset and full double-precision arithmetic, so results match a manual calculation to the displayed number of digits.
Does the Time Zone Converter work on mobile and offline?
Yes. The Time Zone Converter runs entirely in your browser on phones, tablets and desktops, and your inputs never leave your device.
Where can I find related tools?
OneCalcApp hosts 300+ calculators and converters, including the full Date & Time collection. Related tools are linked at the bottom of every page.
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