How to Calculate Your Universal Time Offset

Universal Time, often abbreviated UT or UTC, is more or less the same as Greenwich Mean Time (GMT). Some astronomy tools require that you know the offset, or time difference, between UT and your time zone. The offset can also be used to convert UT to your local time.

You can look up your offset here:

Map-based lookup
Text-based lookup

If you're on Daylight Saving Time (DST), you may have to add one hour to the offset, depending on the tool. Note that if your offset is e.g., -8 hours, it becomes -7 hours with DST (not -9).