IST to ACST Converter

It takes three quick steps:

1. Click the IST field on the left and pick the time you want to convert.
2. The matching ACST time updates on the right automatically — there’s no button to press.
3. Need a different day? Click the date field and the result follows, rolling over if it crosses midnight.

ACST is 4 hours ahead of IST. In everyday terms, once you know the time on one side you just add 4 hours to get the other — so a call between Mumbai and Adelaide is always 4 hours apart.

Right now the time in Australian Central Standard Time (ACST) is Tuesday, June 30, 2026 · 3:24:01 AM. It ticks every second, so you’re always looking at the live ACST clock.

And in India Standard Time (IST), it’s currently Monday, June 29, 2026 · 11:24:01 PM. Compare the two and the 4 hours gap is easy to see.

For example, a 9:00 AM IST meeting takes place at 1:00 PM ACST. The trick is to aim for a slot that lands inside normal working hours on both sides. Once you’ve found a time, hit Share on the converter to copy a link with the time built in — easy to send to a colleague. Juggling three or more zones? The meeting planner highlights the hours that overlap for everyone.

The labels IST and ACST are fixed offsets, so the result on this page is always exact. One side switches between standard and summer time while the other stays put, so the real-world gap can shift by an hour for part of the year. It's worth checking which label a region is actually using before you lock in a time.

Every conversion here is calculated from the IANA time zone database — the same source your phone, computer, and browser rely on. Plenty of tools hard-code a single offset, which quietly goes wrong whenever a region changes its rules or flips for daylight saving. We follow the real rules instead, so IST to ACST stays accurate for today and for any past or future date you type in.