Understanding PST and EST
PST stands for Pacific Standard Time, UTC−8, used in Western North America. EST stands for Eastern Standard Time, UTC−5, used in Eastern North America. These are specific offset definitions, not automatic substitutes for the local time in a city.
How do you convert PST to EST?
Subtract the source offset from the destination offset: -300 − (-480) = 180 minutes. Add 180 minutes from the PST time. For example, 9:00 AM PST is 12:00 PM EST (same day). If the result crosses midnight, the calendar day changes too.
Does daylight saving time change this conversion?
The difference between these named offsets is fixed. A location may switch to a different abbreviation during daylight saving time, so an invitation saying “EST” can differ from the actual summer time in New York.
PST here means North American Pacific Standard Time. Most US Pacific locations use PDT (UTC−7) in summer.
EST is always UTC−5. New York and most US Eastern locations use EDT (UTC−4) during daylight saving time.
Which day does the converted time fall on?
“Previous day” means the destination is one calendar day before the source; “Next day” means one day after. Dates are relative to the day of your input time. A time-only conversion cannot determine a specific calendar date.