Convert IST to AST — Time Difference Between India Standard Time and Atlantic Standard Time

How to Convert IST to AST

Drag the slider on the IST timeline to pick your time — the AST time updates instantly. You can also click the time display to type a specific hour or pick one from the 15-minute interval dropdown, and use the date picker to check a different day.

What Is the Time Difference Between IST and AST?

Atlantic Standard Time (AST) is 9:30 hours behind India Standard Time (IST). To convert, subtract 9:30 hours — for example, 9:00 AM IST is 11:30 PM (previous day) AST.

IST to AST Quick Reference

IST to AST Meeting Planner

Use the color-coded table above to find overlapping work hours between Kolkata and San Juan. Amber rows mark daytime hours — pick a slot that falls in amber on both sides for a meeting that works for everyone.

Why Trust This IST to AST Converter?

Timezoney uses the IANA Time Zone Database — the same source that powers your phone and computer — so every conversion handles daylight saving transitions and half-hour offsets automatically.