IST time now (India Standard Time)
6:22PMIST
UTC+5:30+10 h 30 min vs New York (you)Kolkata now: IST, UTC+5:30
What IST means
IST stands for India Standard Time, UTC+5:30. It is used in India (and Sri Lanka on the same offset).
IST is ambiguous. It also means Israel Standard Time (UTC+2, Israel, in winter) and Irish Standard Time (UTC+1, Ireland, in summer). This page shows UTC+5:30, the meaning English searchers usually want.
IST means three different things
IST is the standard abbreviation of India Standard Time, UTC+5:30, the single time of all of India (Sri Lanka uses the same offset). The same letters are used for Israel Standard Time (UTC+2, in winter) and Irish Standard Time (UTC+1, Ireland’s summer time). tzdata uses IST for all three.
The spread is 3½ hours, enough to wreck a meeting. A message from Dublin in August saying “10:00 IST” means 09:00 UTC; the same text from Tel Aviv in January means 08:00 UTC, and from Bengaluru 04:30 UTC. When the context is not obvious, write UTC+5:30 or the city.
India Standard Time has stayed at UTC+5:30 without daylight saving time since 1945, according to tzdata. Israel changes clocks between IST and IDT (UTC+3) every year.
Where and when IST is used
1 zone uses IST all year. Computed from tzdata under the current rules.
| Main city | Time zone | Countries | When |
|---|---|---|---|
| Mumbai | Asia/Kolkata | India | all year |
Other meanings of IST
| Meaning | Offset | Where | Time now there |
|---|---|---|---|
| India Standard Time | UTC+5:30 | India (and Sri Lanka on the same offset) | 6:22 PM |
| Israel Standard Time | UTC+2 | Israel, in winter (Jerusalem) | 2:52 PM IST |
| Irish Standard Time | UTC+1 | Ireland, in summer (Dublin) | 12:52 PM GMT |
When a time arrives with only these letters, look at where the sender is, or ask for the UTC offset. Calendars and programs should never guess a zone from an abbreviation: the IANA database’s own documentation calls abbreviations ambiguous in practice.
How long IST has been used
In the tzdata record, Mumbai has used IST since 1905.
IST in the past
Zones whose tzdata history shows IST before 2025 but that no longer use it:
- Europe/Dublin (Dublin): 1916–2024
- Asia/Jerusalem (Jerusalem): 1917–2024
- Asia/Gaza (Gaza): 1967–1995
- Asia/Hebron (East Jerusalem): 1967–1995
IST converted to other zones
Every column is a fixed offset, so this table is valid on any date. Remember that the regions behind some columns switch to summer time (EST to EDT, CET to CEST, GMT to BST); the clock in those cities is then an hour later than the column.
| IST (UTC+5:30) | UTC (UTC+0) | EST (UTC−5) | PST (UTC−8) | CET (UTC+1) | JST (UTC+9) | AEST (UTC+10) | CST (UTC−6) |
|---|---|---|---|---|---|---|---|
| 12:00 AM | 6:30 PM (−1 day) | 1:30 PM (−1 day) | 10:30 AM (−1 day) | 7:30 PM (−1 day) | 3:30 AM | 4:30 AM | 12:30 PM (−1 day) |
| 6:00 AM | 12:30 AM | 7:30 PM (−1 day) | 4:30 PM (−1 day) | 1:30 AM | 9:30 AM | 10:30 AM | 6:30 PM (−1 day) |
| 9:00 AM | 3:30 AM | 10:30 PM (−1 day) | 7:30 PM (−1 day) | 4:30 AM | 12:30 PM | 1:30 PM | 9:30 PM (−1 day) |
| 12:00 PM | 6:30 AM | 1:30 AM | 10:30 PM (−1 day) | 7:30 AM | 3:30 PM | 4:30 PM | 12:30 AM |
| 3:00 PM | 9:30 AM | 4:30 AM | 1:30 AM | 10:30 AM | 6:30 PM | 7:30 PM | 3:30 AM |
| 6:00 PM | 12:30 PM | 7:30 AM | 4:30 AM | 1:30 PM | 9:30 PM | 10:30 PM | 6:30 AM |
| 9:00 PM | 3:30 PM | 10:30 AM | 7:30 AM | 4:30 PM | 12:30 AM (+1 day) | 1:30 AM (+1 day) | 9:30 AM |