What is the time difference between IST and JST?

Japan Standard Time (JST) is 3 hours and 30 minutes ahead of India Standard Time (IST). IST uses a UTC offset of UTC+5:30, while JST uses UTC+9. For example, when it's 9:00 AM in IST, it's 12:30 PM in JST. This difference remains constant year-round since neither timezone observes daylight saving time. Use the conversion table above to see the exact time for each hour of the day.

How do I convert IST to JST?

To convert IST to JST, add 3 hours and 30 minutes to the IST time. For example, 9:00 AM IST is 12:30 PM JST, and 5:00 PM IST is 8:30 PM JST. Since neither timezone observes DST, this conversion stays the same all year. You can also use the interactive converter above for quick, accurate results.

What time is it in JST when it's noon in IST?

When it's 12:00 PM (noon) in IST, it's 3:30 PM in JST. This is because JST is 3 hours and 30 minutes ahead of IST. Similarly, when it's 6:00 PM in IST, it's 9:30 PM in JST. This relationship is constant throughout the year. The color-coded conversion table above shows every hour mapped between both timezones.

How many hours ahead is JST from IST?

JST is 3 hours and 30 minutes ahead of IST. This means when it's 9:00 AM in IST, it's 12:30 PM in JST, and when it's midnight in IST, it's 3:30 AM in JST. This offset is constant throughout the year since neither timezone uses daylight saving time. The conversion table above provides a complete hour-by-hour mapping.

Is JST ahead or behind IST?

JST is ahead of IST by 3 hours and 30 minutes. Clocks in JST show a later time than IST, meaning the day starts earlier in JST relative to IST. For example, when it's morning in IST, it's later in the morning in JST. This difference stays the same year-round.

Does IST observe daylight saving time?

No, India Standard Time does not observe daylight saving time. The UTC offset of UTC+5:30 remains the same year-round, making time conversions from IST more predictable. Countries and regions in this timezone keep their clocks unchanged regardless of the season.

Does JST observe daylight saving time?

No, Japan Standard Time does not observe daylight saving time. The UTC offset of UTC+9 remains the same year-round, making time conversions to JST more predictable. Countries and regions in this timezone keep their clocks unchanged regardless of the season.

What is the best time to call from IST to JST?

The best time for a call between IST and JST is during overlapping business hours (9 AM – 5 PM) in both timezones. To reach someone in JST during their work day, call between 5:30 AM and 1:30 PM your IST time. Avoid calling too early or late, as the 3 hours and 30 minutes difference means your evening could be their late night. Check the color-coded conversion table above — green hours indicate business hours in both zones, making it easy to find the ideal time.

Do IST and JST ever have the same time?

No, IST and JST are always 3 hours and 30 minutes apart and never display the same clock time simultaneously. Neither timezone observes DST, so the difference is constant year-round with no seasonal variation. The 3 hours and 30 minutes offset is determined by their fixed positions relative to the Prime Meridian (UTC). You can always rely on this consistent difference when planning across these timezones.

IST to JST Converter

Convert India Standard Time to Japan Standard Time. See the hour-by-hour conversion table below.

Timezone Details

India Standard Time

9:03 PM

Tuesday, June 9, 2026

IST (UTC+05:30)

Japan Standard Time

12:33 AM

Wednesday, June 10, 2026

JST (UTC+09:00)

Difference: +3h 30m

IST DST: No

JST DST: No

24-Hour Overview

IST — 24-hour overview

12a12a

3a3a

6a6a

9a9a

10a

11a

12p12p

3p3p

6p6p

9p9p

10p

11p

NightMorningBusinessEvening

JST — 24-hour overview

3a3a

6a6a

9a9a

10a

11a

12p12p

3p3p

6p6p

9p9p

10p

11p

12a12a

NightMorningBusinessEvening

Frequently Asked Questions

Related Conversions

JST to IST EST to IST IST to EST EST to JST JST to EST PST to IST IST to PST PST to JST JST to PST

Cities in These Timezones

IST Cities

Delhi Mumbai Kolkata Bangalore Chennai

JST Cities

Tokyo Osaka Fukuoka

More Tools

Compare IST & JST Plan a Meeting (IST & JST)See on Map

Learn More

How Time Zones Work Understanding DST Timezone Abbreviations

External Resources

India Standard Time on Wikipedia Japan Standard Time on Wikipedia IANA Time Zone Database