Timezone Converter (JST/UTC and IANA Time Zones)

Q: "How is DST handled?"

"If you specify an IANA time zone (for example, America/New_York), DST is applied automatically for that date/time. Niðurstaðas may depend on the runtime time zone database."

Q: "Can I see date rollovers?"

"Yes. If the source and target dates differ, the verkfæri shows a rollover badge and the day difference."

Q: "Can I do bulk conversion?"

"Yes. You can paste multiple lines and convert each line independently, then copy the niðurstaða as CSV/TSV. Errors in one line do not stop the others."

Q: "Is JST always UTC+9?"

"Japan Standard Time is currently operated as UTC+9."

Q: "Which format should I paste into meeting invites?"

"Use the display format for humans and ISO 8601 for kerfi integration."

Convert date and time instantly between JST, UTC, and IANA time zones.

Handle day rollovers, bera saman multiple zones, share with URL state, and copy niðurstaðas in one skjár.

Fast JST↔UTC conversion

Clear rollover highlight (previous/next day)

Share and restore with URL state

What This Verkfæri Can Do

Bidirectional conversion between JST and UTC
Date and time conversion using IANA zones worldwide
Previous/next-day rollover badges
Batch multi-line conversion with CSV/TSV copy
World clock view for the same instant across zones

How to Use

Select the source time zone and date/time.
Choose one or more target time zones.
Copy display or ISO format, then share as needed.

Common Conversion Examples

JST to UTC

Inntak

2026-01-31 09:00 JST

Úttak

2026-01-31 00:00 UTC

Day rollover (previous day)

Inntak

2026-01-01 00:30 JST

Úttak

2025-12-31 15:30 UTC (Previous day -1)

What Is a Time Zone?

UTC

Coordinated Universal Time. The global baseline for local times.

IANA Time Zone

A region-based identifier such as Asia/Tokyo that reflects local rules, including DST.

Abbreviations (JST/PST etc.)

Abbreviations can be ambiguous. IANA zone IDs are recommended.

Athugasemdir

DST is applied automatically when you use IANA time zones.
Niðurstaðas can vary slightly depending on the runtime time zone database version.
On DST transition dates, some local times may not exist or may occur twice.

Algengar spurningar

How is DST handled?

If you specify an IANA time zone (for example, America/New_York), DST is applied automatically for that date/time. Niðurstaðas may depend on the runtime time zone database.

Can I see date rollovers?

Yes. If the source and target dates differ, the verkfæri shows a rollover badge and the day difference.

Can I do bulk conversion?

Yes. You can paste multiple lines and convert each line independently, then copy the niðurstaða as CSV/TSV. Errors in one line do not stop the others.

Is JST always UTC+9?

Japan Standard Time is currently operated as UTC+9.

Which format should I paste into meeting invites?

Use the display format for humans and ISO 8601 for kerfi integration.