Convert IST to PST India Standard Time ↔ Pacific Standard Time Free Online Secure
Type a time in IST and read it in PST straight away. The offset is −13:30 h, the arithmetic wraps at midnight, and the answer says which day it lands on.
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Through the day — Convert IST to PST (India Standard Time ↔ Pacific Standard Time)
| IST | PST |
|---|---|
| 00:00 | 10:30 |
| 03:00 | 13:30 |
| 06:00 | 16:30 |
| 09:00 | 19:30 |
| 12:00 | 22:30 |
| 15:00 | 01:30 |
| 18:00 | 04:30 |
| 21:00 | 07:30 |
Where these units come from
Until the middle of the nineteenth century every town kept its own noon, set by the sun overhead, and nobody minded that the next town was four minutes behind. Railways ended that: a timetable cannot be written for a hundred local noons. Britain put its railways on Greenwich time in 1847, and in 1884 the International Meridian Conference in Washington chose Greenwich as the prime meridian and sketched the twenty-four-hour scheme we still use. Greenwich Mean Time was the world's reference until 1972, when Coordinated Universal Time replaced it: UTC is kept by atomic clocks and tied back to the turning Earth by leap seconds. The abbreviations on this page name standard time — the winter setting — which is why each one is a fixed number of hours rather than something that drifts through the year.
Where you meet them
A time zone becomes real the moment two people in different places have to agree on one moment: a call between offices, a flight that lands before it took off, a market that opens while you are asleep, a deadline written in somebody else's afternoon. Server logs, train and flight schedules and anything stamped with a time are kept in UTC precisely so that the question can always be settled, no matter whose clock was on the wall.
Questions people ask
What about summer time?
The offsets here are standard-time offsets, the ones a zone keeps in winter. Where summer time is observed, the same places move one hour further on for part of the year and take a different name: Central European Time becomes Central European Summer Time, Eastern Standard Time becomes Eastern Daylight Time. The switching dates are not the same in every country, and the two hemispheres change in opposite months, so for a date inside a summer-time period add an hour to whichever side observes it.
Why isn't every difference a whole number of hours?
Because offsets are decided by governments, not by geometry. India is half an hour off the hour, at UTC+05:30; Nepal is three quarters, at UTC+05:45; the Chatham Islands are at UTC+12:45. Any of these can be changed by law, and several countries have moved their offset within living memory.
Is the answer exact?
Where both units are defined in terms of one another by whole numbers, yes — the page says so above the figure, and the only rounding is in how many digits are shown. Where the ratio has no finite decimal, the page shows twelve significant digits and says the relation is approximate rather than pretending otherwise.
Does anything I type leave my device?
No. The arithmetic runs in your browser; nothing is uploaded and there is no server to upload it to. Load the page once and it keeps working with the network switched off.
From India to California: the hour on the poster, the hour on the clock
Railway bookings open in India at 08:00 IST. The prime minister’s Independence Day address begins at 07:30. A session of the Mumbai exchange closes at 15:30. For someone in Los Angeles, San Francisco or Seattle, each of those hours calls for a “convert IST to PST” calculation. In winter the calculation is a subtraction: thirteen and a half hours. 08:00 IST becomes 18:30 PST on the previous day, 15:30 IST becomes 02:00 PST, and 19:30 IST becomes 06:00 PST. Any Indian time before 13:30 belongs to the previous day in California. From 8 March to 31 October, with PDT in place of PST, only twelve and a half hours are subtracted.
The page starts with Indian events followed in the American west, then shows the rule, the tables and the two zones. Everything is calculated in the browser; nothing goes to a server.
Railway bookings, on a Californian evening
When the online counter opens
Last-minute (Tatkal) bookings open at 10:00 IST, which is 8:30 p.m. PST on the previous evening. Californians booking tickets for family stay up or set an alarm late in the evening.
Ordinary bookings
Ordinary bookings open at 08:00 IST, which is 6:30 p.m. PST. A “convert IST to PST” calculation shows at once that on the Californian clock the hour falls at the end of the working day.
15 August: the speech at the Red Fort
The flag and the address
The ceremony begins at 07:30 IST, which is 7:00 p.m. PDT on the evening of 14 August, because in August America is on summer time and the gap is twelve and a half hours. The Indian community in California watches after work.
The evening of the holiday
Cultural programmes at 19:30 IST are at 7:00 a.m. PDT. A “convert IST to PST” calculation made beforehand shows that they fall in the first hour of the Californian morning.
The Mumbai exchange and the Nasdaq
The two timetables
The Indian exchange trades from 09:15 to 15:30 IST, which is 7:45 p.m. PST on the previous evening to 2:00 a.m. PST. The Nasdaq trades from 6:30 a.m. to 1:00 p.m. PST. The two sessions never overlap.
The gap between them
Between the Mumbai close at 2:00 a.m. PST and the Nasdaq opening at 6:30 a.m. PST lie four and a half hours. A “convert IST to PST” calculation for each line of the timetable shows in which window fresh news can move the markets.
India’s budget speech
Presentation in Parliament
The finance minister presents the budget at 11:00 IST, which is 9:30 p.m. PST on the previous evening. Californian analysts follow late in the evening or read the summary in the morning.
The market’s reaction
The Mumbai exchange reacts in that same session, which ends at 2:00 a.m. PST, four and a half hours before the Nasdaq opens.
The cricket World Cup final
The start time
A final that starts at 14:00 IST starts at 12:30 a.m. PST, in the Californian night. Fans in the west stay up or watch the highlights in the morning.
Evening matches
A match at 19:00 IST starts at 5:30 a.m. PST, at dawn. A “convert IST to PST” calculation made in good time shows whether you need to set an alarm.
The Kolkata book fair
Opening the gates
The fair usually opens its gates at midday, 12:00 IST, which is 10:30 p.m. PST on the previous evening. Californians following the event online catch it at the end of their day.
The cultural programme
Evening book launches, from 18:00 IST, are at 4:30 a.m. PST. A “convert IST to PST” calculation made beforehand shows whether they fall at dawn or at night.
Bollywood releases
The evening premiere
A premiere scheduled for 18:00 IST begins at 4:30 a.m. PST. Fans in the diaspora watch at dawn, on the way to work or over coffee.
The online release
A film released on a platform at 00:00 IST appears at 10:30 a.m. PST on the previous day. Californians can therefore see it before Indians do.
How to convert IST to PST, stage by stage
Stage one: the subtraction
IST sits at UTC+5:30 and the Pacific in winter at UTC−8. The clocks are 13 hours 30 minutes apart, with India ahead. Write the Indian time on a 24-hour clock and subtract 13:30.
Stage two: the date
A negative result calls for the previous day: add 24. For example, 03:30 IST gives 14:00 PST yesterday, 07:00 IST gives 17:30 PST yesterday, and 10:00 IST gives 20:30 PST yesterday.
Stage three: the check
13:30 IST is 00:00 PST. 16:45 IST is 03:15 PST. 19:30 IST is 06:00 PST. 22:15 IST is 08:45 PST. 23:59 IST is 10:29 PST. With PDT, 19:30 IST is 07:00 PDT, an hour later.
The Pacific in brief
Where to find it
From the Mexican border to British Columbia, the winter clock stands at UTC−8: California, Oregon, Washington and most of Nevada. In spring they move to UTC−7 under the name PDT.
Why it concerns you
Anyone living in the west who wants to follow an Indian event live cannot trust the time on the poster. Californians therefore often convert IST to PST.
Indian time in brief
One clock
From Gujarat to Assam India uses the same clock, UTC+5:30, in every month. The half hour changes the minutes of the result: 19:15 IST becomes 05:45 PST.
The neighbours
Sri Lanka has the same time as India. Nepal has UTC+5:45, Pakistan UTC+5 and Bangladesh UTC+6.
Thirteen and a half hours on the dial
The working days
A Delhi office open from 09:00 to 17:00 works, on the Pacific clock, from 19:30 to 03:30 of the previous day. A Californian one open from 09:00 to 17:00 works from 22:30 to 06:30 on Indian time. The two schedules have no hour in common.
Calls
A call from India at 20:30 IST rings at 7:00 a.m. PST, too early for many. One from 23:30 IST rings at 10:00 a.m. PST, in mid-morning in California.
The flight over the Pacific
A plane with one stop that takes off from Bangalore at 02:00 IST and flies for nearly twenty-one hours comes down in San Francisco at 23:00 IST, which is 9:30 a.m. PST. The ticket shows 02:00 and 23:00, as for a trip of twenty-one hours, while the Californian clock shows the departure was on the afternoon of the previous day.
Holi and the spring festivals
The morning of colours
The festival of colours begins in the morning, around 08:00 IST, which is 6:30 p.m. PST on the previous evening if the date falls before 8 March. After America moves to summer time, that hour means 7:30 p.m. PDT.
The broadcasts
Online broadcasts for the diaspora start at 10:00 IST, which is 8:30 p.m. PST. A “convert IST to PST” calculation tells you at once whether the date falls before or after the change of clocks.
Durga Puja in Kolkata
The evening rites
The main evening ritual starts at 19:00 IST, which is 5:30 a.m. PST or 6:30 a.m. PDT, depending on the date. Americans in the west watch at dawn.
The processions
Morning processions, from 10:00 IST, are in California on the previous evening, at 9:30 p.m. PDT in October. A “convert IST to PST” calculation tells you at once on which day the event falls.
Four dates from the calendar
Midwinter
On Saturday 17 January, 10:00 IST is 20:30 PST on Friday 16 January.
The end of February
On Saturday 28 February, 10:00 IST is still 20:30 PST on Friday: California has not yet moved its clock.
Mid-March
On Saturday 14 March, 10:00 IST is 21:30 PDT on Friday, because California went onto summer time on 8 March and India did not.
August and November
On Saturday 15 August, 10:00 IST is 21:30 PDT on Friday. On Saturday 14 November, 10:00 IST is again 20:30 PST on Friday, after California’s return to standard time on 1 November.
Support centres for customers in the west
The evening shift
A centre in India starts its shift at 19:00 IST, which is 5:30 a.m. PST. The first calls come from early-rising Californians.
The handover
At 03:30 IST, which is 2:00 p.m. PST of the previous day, the shift ends and the Californian colleagues take over the open cases. A “convert IST to PST” calculation at each handover shows who is working at that moment.
More clocks, read from Delhi
The differences at a glance
Relative to Delhi: Berlin is 4:30 behind, London 5:30, New York 10:30, Chicago 11:30, Denver 12:30 and Los Angeles 13:30, all in winter time. Tokyo is 3:30 ahead.
One instant on five dials
When it is 20:30 in Delhi, it is 15:00 in London, 16:00 in Berlin, 10:00 in New York and 7:00 in Los Angeles. Whoever puts all the hours in the invitation spares the guests a “convert IST to PST” calculation.
Remote medical consultations
Booking
A consultation booked for 20:00 IST is at 6:30 a.m. PST. Indian doctors see Californian patients in the evening, after clinic hours, while the patients log on before work.
Prescriptions
A prescription issued at 09:00 IST on 5 March was issued at 7:30 p.m. PST on 4 March. A “convert IST to PST” calculation made with the date in view shows the exact day of issue.
Online courses from Indian institutions
Course time
A lecture at 19:00 IST is at 5:30 a.m. PST. Californian students follow it at dawn, before work.
Deadlines
A deadline of 23:59 IST falls at 10:29 a.m. PST on the same day. Whoever counts the deadline by home midnight loses whole hours.
How the clock changes affect this pair
The 2026 calendar
The gap between IST and PST changes during the year. In 2026: 1 January to 7 March and 1 November to 31 December — PST runs 13 hours 30 minutes behind IST; 8 to 28 March, 29 March to 24 October and 25 to 31 October — PST runs 12 hours 30 minutes behind IST.
What to do about it
In the summer periods the labels are IST and PDT. The calculator above uses the winter gap of 13 hours 30 minutes. For other dates, adjust the result by the difference between that figure and the gap listed for the period. Before you convert IST to PST, find the period that contains your date.
A day of conversions at a glance
IST into PST
00:00 IST = 10:30 PST (previous day). 01:00 IST = 11:30 PST (previous day). 02:00 IST = 12:30 PST (previous day). 03:00 IST = 13:30 PST (previous day). 04:00 IST = 14:30 PST (previous day). 05:00 IST = 15:30 PST (previous day). 06:00 IST = 16:30 PST (previous day). 07:00 IST = 17:30 PST (previous day). 08:00 IST = 18:30 PST (previous day). 09:00 IST = 19:30 PST (previous day). 10:00 IST = 20:30 PST (previous day). 11:00 IST = 21:30 PST (previous day). 12:00 IST = 22:30 PST (previous day). 13:00 IST = 23:30 PST (previous day). 14:00 IST = 00:30 PST. 15:00 IST = 01:30 PST. 16:00 IST = 02:30 PST. 17:00 IST = 03:30 PST. 18:00 IST = 04:30 PST. 19:00 IST = 05:30 PST. 20:00 IST = 06:30 PST. 21:00 IST = 07:30 PST. 22:00 IST = 08:30 PST. 23:00 IST = 09:30 PST.
Using the table
Find the IST hour you need and read off the PST hour beside it. The rows come from the arithmetic behind each request to convert IST to PST. The half-hour in the offset moves each minute reading by thirty, which is why this pair needs a second look. Read these rows as standard-time values and check the period section for dates where the difference changes.
The :30 rows
IST to PST, thirty minutes past
00:30 IST = 11:00 PST (previous day). 01:30 IST = 12:00 PST (previous day). 02:30 IST = 13:00 PST (previous day). 03:30 IST = 14:00 PST (previous day). 04:30 IST = 15:00 PST (previous day). 05:30 IST = 16:00 PST (previous day). 06:30 IST = 17:00 PST (previous day). 07:30 IST = 18:00 PST (previous day). 08:30 IST = 19:00 PST (previous day). 09:30 IST = 20:00 PST (previous day). 10:30 IST = 21:00 PST (previous day). 11:30 IST = 22:00 PST (previous day). 12:30 IST = 23:00 PST (previous day). 13:30 IST = 00:00 PST. 14:30 IST = 01:00 PST. 15:30 IST = 02:00 PST. 16:30 IST = 03:00 PST. 17:30 IST = 04:00 PST. 18:30 IST = 05:00 PST. 19:30 IST = 06:00 PST. 20:30 IST = 07:00 PST. 21:30 IST = 08:00 PST. 22:30 IST = 09:00 PST. 23:30 IST = 10:00 PST.
Purpose of the list
These are the readings people forget to check: events at :30. Look up the IST time and read the PST time beside it instead of repeating the calculation. The gap used here is the standard winter one; the period section lists the dates on which it differs.
Odd times, converted
Ten IST times and their PST equivalents
01:05 IST = 11:35 PST (previous day). 03:20 IST = 13:50 PST (previous day). 05:50 IST = 16:20 PST (previous day). 07:35 IST = 18:05 PST (previous day). 10:10 IST = 20:40 PST (previous day). 13:25 IST = 23:55 PST (previous day). 16:40 IST = 03:10 PST. 19:55 IST = 06:25 PST. 22:15 IST = 08:45 PST. 23:05 IST = 09:35 PST.
Observation
Real schedules are rarely on the hour, so here are ten with awkward minutes. Because of the half hour, the minute figure always shifts by thirty; expect :15 to become :45 and :45 to become :15. Winter-time arithmetic applies to these rows; for the dates in the period section, correct the result accordingly.
Times of day in PST
A day in IST, translated into PST
06:00 IST = 16:30 PST (afternoon). 08:00 IST = 18:30 PST (evening). 10:00 IST = 20:30 PST (evening). 12:00 IST = 22:30 PST (night). 14:00 IST = 00:30 PST (night). 16:00 IST = 02:30 PST (night). 18:00 IST = 04:30 PST (night). 20:00 IST = 06:30 PST (early morning). 22:00 IST = 08:30 PST (morning).
A practical tip
Read down the list to see how the IST day maps onto the PST day. It is useful before you convert IST to PST for a meeting invitation. Read these rows as standard-time values and check the period section for dates where the difference changes.
Before you convert IST to PST: a short checklist
Preparation
Confirm the zones
Indian Standard Time is UTC+5:30; the same three letters are used for Israel and for Ireland’s summer clock, which this page does not cover. Pacific Standard Time is UTC−8; the letters PST are also used for the Philippines and for Pakistan, which are not covered here.
Use a 24-hour clock
Turn a.m. and p.m. into the 24-hour form first: 4:30 p.m. is 16:30 and 12:00 a.m. is 00:00. For example, 09:15 IST becomes 19:45 PST (previous day).
Then
The operation
Subtract 13 hours 30 minutes. If the result passes midnight, correct the date: readings before 13:30 fall on the previous date.
A second example
An evening check: 22:40 IST gives 09:10 PST.
Common slips when you convert IST to PST
Adding instead of subtracting
Because PST runs behind IST, the result must be an earlier clock reading. A later one points to an addition.
Losing the date
Anything on the IST clock before 13:30 lands on the previous date. Forgetting to move the date leaves the result 24 hours wrong.
The standard figure in the wrong weeks
Do not assume that IST and PST are always the same distance apart; the period list above shows the exceptions.
Confusing the abbreviation
The letters IST are shared with Ireland’s summer clock and Israel’s standard time; this page means India. Pacific Standard Time is UTC−8; the letters PST are also used for the Philippines and for Pakistan, which are not covered here.
Questions and answers
How far apart are IST and PST?
13 hours 30 minutes, and PST is behind IST. That is the standard figure; on some dates in 2026 it differs, as the period list shows.
What do I do to convert IST to PST?
Subtract 13 hours 30 minutes from the IST time, then fix the date if the result passes midnight.
What does 15:30 IST become in PST?
02:00 PST in the standard period.
Is the gap the same in every month?
No, it differs on some dates; the period list above shows which.
Is the time I enter sent anywhere?
No. Everything happens on your own device.
Other pairs worth a look
Related pages: Convert IST to EST, Convert IST to CST, Convert GMT to PST, Convert CST to PST, Convert PST to UTC, Convert EST to IST, Convert CST to EST, Convert CST to CET, Convert EST to UTC. For the reverse direction, open Convert PST to IST.
That is all there is to it. To convert IST to PST, subtract 13 hours 30 minutes; nothing leaves your browser.