GMT to PST converter
Pacific Time is 8 hours behind GMT in winter (PST, UTC−8) and 7 hours behind in summer (PDT, UTC−7). To convert GMT to PST, subtract 8 hours during standard time and 7 hours during daylight saving time. Only Pacific Time moves its clocks, so nothing else changes the gap.
GMT runs at UTC+0, Pacific Time at UTC−8 / UTC−7.
GMT to PST conversion table
Every hour of the day converted for both halves of the year. The two columns differ because Pacific Time changes its offset for daylight saving time.
| GMT (GMT) | PST (Nov–Mar) | PDT (Mar–Nov) |
|---|---|---|
| 00:00 12:00 AM | 16:00 4:00 PM previous day | 17:00 5:00 PM previous day |
| 01:00 1:00 AM | 17:00 5:00 PM previous day | 18:00 6:00 PM previous day |
| 02:00 2:00 AM | 18:00 6:00 PM previous day | 19:00 7:00 PM previous day |
| 03:00 3:00 AM | 19:00 7:00 PM previous day | 20:00 8:00 PM previous day |
| 04:00 4:00 AM | 20:00 8:00 PM previous day | 21:00 9:00 PM previous day |
| 05:00 5:00 AM | 21:00 9:00 PM previous day | 22:00 10:00 PM previous day |
| 06:00 6:00 AM | 22:00 10:00 PM previous day | 23:00 11:00 PM previous day |
| 07:00 7:00 AM | 23:00 11:00 PM previous day | 00:00 12:00 AM |
| 08:00 8:00 AM | 00:00 12:00 AM | 01:00 1:00 AM |
| 09:00 9:00 AM | 01:00 1:00 AM | 02:00 2:00 AM |
| 10:00 10:00 AM | 02:00 2:00 AM | 03:00 3:00 AM |
| 11:00 11:00 AM | 03:00 3:00 AM | 04:00 4:00 AM |
| 12:00 12:00 PM | 04:00 4:00 AM | 05:00 5:00 AM |
| 13:00 1:00 PM | 05:00 5:00 AM | 06:00 6:00 AM |
| 14:00 2:00 PM | 06:00 6:00 AM | 07:00 7:00 AM |
| 15:00 3:00 PM | 07:00 7:00 AM | 08:00 8:00 AM |
| 16:00 4:00 PM | 08:00 8:00 AM | 09:00 9:00 AM |
| 17:00 5:00 PM | 09:00 9:00 AM | 10:00 10:00 AM |
| 18:00 6:00 PM | 10:00 10:00 AM | 11:00 11:00 AM |
| 19:00 7:00 PM | 11:00 11:00 AM | 12:00 12:00 PM |
| 20:00 8:00 PM | 12:00 12:00 PM | 13:00 1:00 PM |
| 21:00 9:00 PM | 13:00 1:00 PM | 14:00 2:00 PM |
| 22:00 10:00 PM | 14:00 2:00 PM | 15:00 3:00 PM |
| 23:00 11:00 PM | 15:00 3:00 PM | 16:00 4:00 PM |
How the GMT to PST conversion works
Converting GMT to PST means taking a wall-clock time in GMT (GMT, UTC+0) and expressing the same instant in Pacific Time (PST / PDT, UTC−8 / UTC−7). The arithmetic is one step: subtract 8 hours while Pacific Time is on standard time, and 7 hours while it is on daylight saving time. Applying the gap pushes part of the day onto a different calendar date — the table below marks every row that shifts. In code, store the instant in UTC and convert with the IANA identifiers Etc/GMT and America/Los_Angeles, never with the abbreviations. On the target label: PST strictly names the winter offset, so a summer meeting written as PST is almost always PDT, an hour earlier. IANA identifiers carry the full offset history of a region, including every daylight saving transition ever legislated, which is why databases, schedulers, and APIs should store them.
GMT vs UTC
GMT on this page names the fixed Etc/GMT zone, which is identical to UTC+0 every day of the year — the table above is exact regardless of which term you use. It is not the same thing as UK local time: the United Kingdom itself keeps GMT only from late October to late March and observes British Summer Time (UTC+1) the rest of the year, one hour ahead of every GMT value on this page. If your search for GMT meant the UK's current clock rather than the fixed reference offset, check which side of that switch today falls on.
Meant the fixed reference rather than UK local time? UTC to PST reports the same numbers under that name.
Best time for meetings between GMT and PST
Working hours are taken as 09:00–18:00 in each zone. The window in force depends on the date, so both halves of the year are listed where they differ.
PST (Nov–Mar)
A 9-to-6 working day in both zones overlaps for 1 hour: 5:00 PM–6:00 PM GMT is 9:00 AM–10:00 AM PST. Book inside that window and neither side is working outside normal hours.
PDT (Mar–Nov)
A 9-to-6 working day in both zones overlaps for 2 hours: 4:00 PM–6:00 PM GMT is 9:00 AM–11:00 AM PDT. A call booked inside that window keeps both sides within a normal working day.
Daylight saving time: which side moves
Only Pacific Time shifts. GMT holds a single offset all year, so every change in the gap comes from Pacific Time moving between PST (UTC−8) and PDT (UTC−7).
Pacific Time is 8 hours behind GMT through the Nov–Mar window, and 7 hours behind through the Mar–Nov window.
US daylight saving time runs from the second Sunday in March to the first Sunday in November.
- GMT
- Etc/GMT
- GMT — UTC+0
- Pacific Time
- America/Los_Angeles
- PST / PDT — UTC−8 / UTC−7
Frequently asked questions
What is the time difference between GMT and PST?
Pacific Time runs 8 hours behind GMT during standard time and 7 hours behind during daylight saving time. In offset terms, GMT sits at UTC+0 and Pacific Time at UTC−8 / UTC−7. So 9:00 AM GMT is 1:00 AM PST, and 2:00 AM PDT once the clocks change. The hour-by-hour table on this page lists the conversion for all 24 hours so you do not have to do the arithmetic.
Does the GMT to PST difference change with daylight saving time?
The difference does change. Pacific Time moves its clocks, so the gap swings between 8 hours and 7 hours depending on the date. In the US that means clocks move forward on the second Sunday of March and back on the first Sunday of November. GMT here is the fixed UTC+0 standard; the United Kingdom itself leaves GMT for BST (UTC+1) each summer.
What time is 9 am GMT in PST?
9:00 AM GMT is 1:00 AM in Pacific Time during standard time (PST) and 2:00 AM during daylight saving time (PDT). The rule is the same one the whole page runs on: subtract 8 hours in winter and 7 hours in summer. Check the hour-by-hour table for any other starting hour, including the rows that land on the previous or next calendar day.
What do GMT and PST stand for?
GMT stands for Greenwich Mean Time. PST stands for Pacific Standard Time, and PDT is Pacific Daylight Time. Both are display labels rather than rules: the offsets behind them come from the IANA identifiers Etc/GMT and America/Los_Angeles. GMT is fixed at UTC+0 as a time standard, but people often write it when they mean UK local time, which becomes BST in summer.
Related conversions
Need more than two zones at once? The full timezone converter shows a single moment across up to six IANA timezones, for any date you choose.