How many hours is IST ahead of CET?
As abbreviations, CET is always 4.5 hours behind of IST: IST is UTC+5:30 and CET is UTC+1. To convert, subtract 4.5 hours.
Check which label you actually need: CET (Central European Time is on CEST today). A time written with an abbreviation that is not in use is usually meant as the local time, so convert between the places instead: right now CET is 3.5 hours behind of IST.
When the IST to CET time difference changes
For most of the year CET is 3.5 hours behind of IST. From 25 October to 31 December 2026, CET is 4.5 hours behind of IST instead, because the two places change their clocks on different dates. Meetings booked by the usual gap land an hour off in those weeks.
| Dates | CET vs IST | Length |
|---|---|---|
| 29 March 2026 to 24 October 2026 | 3.5 hours behind | 210 days |
| 25 October 2026 to 31 December 2026 | 4.5 hours behind | 68 days |
| 1 January 2027 to 27 March 2027 | 4.5 hours behind | 86 days |
| 28 March 2027 to 30 October 2027 | 3.5 hours behind | 217 days |
| 31 October 2027 to 31 December 2027 | 4.5 hours behind | 62 days |
Best time for a meeting between IST and CET
- When CET is 3.5 hours behind of IST: 4 shared office hours, 13:00 to 17:00 in IST (09:30 to 13:30 in CET).
- When CET is 4.5 hours behind of IST: 3 shared office hours, 14:00 to 17:00 in IST (09:30 to 12:30 in CET).