Convert India Standard Time to Japan Standard Time (IST to JST)

Understanding IST and JST Time Zones

India Standard Time (IST)

India Standard Time is observed in undefined and uses the offset UTC+5.5. Major cities in this time zone include Mumbai, Delhi, Bangalore. This time zone serves a significant global region with important economic and cultural hubs.

Japan Standard Time (JST)

Japan Standard Time operates at UTC+9, covering undefined. Key cities include Tokyo, Osaka, Yokohama. The 3.5-hour forward offset from IST means that when professionals in Mumbai start their workday at 9:00 AM, it is already 12:30 PM in Tokyo.

IST is also commonly referred to as India time, Indian time, Mumbai time, Delhi time. JST is also known as Japan time, Tokyo time, Japanese time. So if you are searching for India time to Japan time, this is the same conversion as IST to JST.

Complete IST to JST Conversion Table

The table below shows every two-hour increment converted from India Standard Time to Japan Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.

Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.

Scheduling Between IST and JST

International conference calls between Mumbai, Delhi, Bangalore and Tokyo, Osaka, Yokohama work best when scheduled during the overlap of both regions' business hours. Rotating meeting times monthly ensures fairness across time zones.

The moderate 3.5-hour gap between IST and JST means that there is a partial overlap of business hours. Teams can typically find a 3–4 hour window that works for both sides without requiring anyone to work outside normal hours.

Travel Between Mumbai and Tokyo

Booking hotels and transportation in Tokyo? Double-check whether listed check-in times are in JST (local) or your departure time zone. A common mistake is arriving 3.5 hours early or late due to unconverted times.

Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 3.5-hour shift between IST and JST, plan for about 3.5 days to fully acclimate.

Daylight Saving Time Considerations

When daylight saving time is in effect, the abbreviation changes (e.g., EST becomes EDT, CET becomes CEST). Our converter handles this automatically, but being aware of which version is active helps avoid confusion.

For the IST to JST conversion specifically: IST (UTC+5.5) and JST (UTC+9) neither observes DST, so the 3.5-hour offset remains constant throughout the year. This makes scheduling reliable and predictable.

Related Time Zone Conversions

References & Resources

• TimeAndDate.com — World Time Zones
• NIST — Official US Time Standard
• IANA Time Zone Database
• Wikipedia — Time Zone Abbreviations
• WorldTimeServer — Current Times Worldwide
• NICT — Official Japanese Time

Frequently Asked Questions