Does it handle Daylight Saving Time?

Yes, the tool automatically adjusts for Daylight Saving Time based on the specific date you select, ensuring accurate conversions year-round.

Can I add multiple cities?

Yes, you can add as many cities as you need to the dashboard to compare times across your entire global network simultaneously.

Osaka to MDT

-15h

Osaka

JSTSOURCE

Japan · UTC+09:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

MDT

UTC-06:00☀ DST active

HH09

MM00

(previous day)21:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Osaka

MDT

12:00 AM

9:00 AM-1

2:00 AM

11:00 AM-1

4:00 AM

1:00 PM-1

6:00 AM

3:00 PM-1

8:00 AM

5:00 PM-1

10:00 AM

7:00 PM-1

12:00 PM

9:00 PM-1

2:00 PM

11:00 PM-1

4:00 PM

1:00 AM

6:00 PM

3:00 AM

8:00 PM

5:00 AM

10:00 PM

7:00 AM

Green rows indicate typical business hours (9 AM - 5 PM)

JST and MDT on the World Map

The map below highlights the JST (Japan Standard Time) and MDT (Mountain Daylight Time) timezone regions across the globe.

JST Zone

→

MDT Zone

Explore all world timezones interactively →

JST – Japan Standard Time

UTC+09:00

Japan Standard Time (JST) is the time zone for Japan, 9 hours ahead of UTC.

Countries in JST

Japan

Major Cities in JST

TokyoOsakaYokohamaNagoyaSapporoKyotoKobeFukuokaHiroshima

Key Facts about JST

•Japan does not observe daylight saving time.
•Tokyo is the most populous metropolitan area in the world.
•The Tokyo Stock Exchange operates from 9:00 AM to 3:00 PM JST.
•JST is 14 hours ahead of EST and 9 hours ahead of GMT.

Daylight Saving:No – UTC+09:00 year-round

Learn more about JST on Wikipedia

MDT – Mountain Daylight Time

UTC-06:00

Mountain Daylight Time (MDT) is the daylight saving offset in the Mountain Time Zone, 6 hours behind UTC.

Countries in MDT

United States (Mountain)Canada (Alberta)

Major Cities in MDT

DenverCalgaryEdmontonSalt Lake CityBoise

Key Facts about MDT

•MDT shares the same offset as CST (UTC-06:00).
•Arizona does not switch to MDT, remaining on MST.

Daylight Saving:Yes – switches to MST

Learn more about MDT on Wikipedia

About Osaka

Wikipedia

Osaka operates on Japan Standard Time (JST), UTC+9. As Japan's second economic center and a manufacturing hub, Osaka shares business hours with Tokyo.

Population:2.8 million

Metro:19 million

Business Hours:9:00 AM - 6:00 PM JST

Currency:JPY (¥)

Stock Exchange:OSE (Osaka Exchange - derivatives)

Key Landmarks

Osaka CastleDotonboriUniversal Studios JapanShitennoji TempleUmeda Sky Building

Did You Know?

Osaka Castle was originally built in 1583 and has been rebuilt several times.

Learn more about JST timezone →

Understanding the -15h Gap: Osaka vs MDT

Osaka runs on Japan Standard Time (JST) at UTC+09:00. MDT runs on Mountain Daylight Time (MDT) at UTC-06:00. That puts Osaka 15 hours behind MDT — a difference of -15h at the current offsets.

In practice, when it is 9:00 AM in Osaka it is 6:00 PM in MDT on the previous day. Midnight in Osaka is 9:00 AM in MDT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Osaka to MDT time conversion table

Osaka (JST)	MDT (MDT)	Day
12:00 AM	9:00 AM	previous day
6:00 AM	3:00 PM	previous day
7:00 AM	4:00 PM	previous day
8:00 AM	5:00 PM	previous day
9:00 AM	6:00 PM	previous day
12:00 PM	9:00 PM	previous day
3:00 PM	12:00 AM	same day
5:00 PM	2:00 AM	same day
6:00 PM	3:00 AM	same day
9:00 PM	6:00 AM	same day

Why people convert Osaka to MDT time

Scheduling a call from Osaka to MDT: a 10:00 AM start in Osaka lands at 7:00 PM in MDT the previous day, so you can confirm the slot without doing the arithmetic yourself.
Handling a -15h gap: Osaka and MDT have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in MDT is 6:00 PM in Osaka.
Keeping family and friends in sync: knowing that 8:00 PM in Osaka is 5:00 AM in MDT makes it easy to avoid calling at 3 AM.

Always state the zone abbreviation, not just the hour. "3:00 PM JST" is unambiguous; "3 PM" across a -15h gap is not.
With a -15h gap there is no shared 9-to-5 window, so alternate the early start: one week Osaka takes the early slot, the next week MDT does.

About JST (Japan Standard Time)

Japan Standard Time (JST) is the standard time zone for all of Japan. Japan does not observe daylight saving time. JST is 9 hours ahead of UTC and 14 hours ahead of EST. The Tokyo Stock Exchange, the world's third largest by market capitalization, operates on JST. South Korea uses the same offset (KST) but it is a distinct time zone.

About MDT (Mountain Daylight Time)

Mountain Daylight Time (MDT) is observed during summer months in the Mountain Time Zone, except in Arizona which stays on MST year-round. MDT aligns with Central Standard Time (CST) at UTC-06:00.

Best time to call between Osaka and MDT

With a -15h offset there is no overlap inside a normal 9 AM – 5 PM day. MDT opens at 9:00 AM MDT, which is 6:00 PM in Osaka, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Osaka and MDT have no shared working hours because of the -15h gap. Teams need to alternate early starts or rely on asynchronous handovers.

Osaka is 15 hours behind MDT (JST UTC+09:00 → MDT UTC-06:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

Osaka

Does not observe DST

MDT

☀ Currently in DST

Standard: UTC-07:00 · DST: UTC-06:00

Clocks fall back on Sun, Nov 1, 2026

Learn More About Time

Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:

⏳

History of Timekeeping

From sundials to atomic clocks - 5000 years of measuring time

🌍

How Time Zones Work

UTC, offsets, and why zones don't follow straight lines

☀️

Daylight Saving Time

DST dates, which countries observe it, and the ongoing debate

Frequently Asked Questions

What is the time difference between Osaka and MDT?

Osaka (JST, UTC+09:00) is 15 hours behind MDT (MDT, UTC-06:00). The gap is currently -15h.

How do I convert Osaka time to MDT time?

Add -15h to Osaka local time. For example, 9:00 AM in Osaka is 6:00 PM in MDT (previous day).

What time is it in MDT right now?

MDT uses MDT at UTC-06:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -15h offset from Osaka.

What is the best time to call MDT from Osaka?

There is no shared working-hours window because of the -15h gap. The closest option is 1:00 PM in Osaka, which is 10:00 PM in MDT.

Which is behind, Osaka or MDT?

Osaka is 15 hours behind MDT. When it is 12:00 PM in Osaka it is 9:00 PM in MDT.

Do Osaka and MDT use different time zones?

Osaka (Japan) uses JST at UTC+09:00, while MDT uses MDT at UTC-06:00. The IANA identifiers are Asia/Tokyo and America/Denver.

Does daylight saving time affect the Osaka–MDT difference?

Neither zone observes daylight saving time, so the -15h offset between Osaka and MDT is fixed all year.

Which other cities share Osaka's time zone?

JST also covers Tokyo, Osaka, Yokohama, Nagoya, Sapporo, Kyoto, Kobe, Fukuoka and 1 more.

Which countries use JST, Osaka's zone?

JST is used in Japan.

Is there a day difference between Osaka and MDT?

Sometimes. The -15h gap is large enough that 8:00 PM or later in Osaka already falls on the in MDT.

What is the time difference between Osaka and MDT?

MDT is -15h from Osaka.

What timezone is Osaka in?

Osaka operates on Japan Standard Time (JST), UTC+9. As Japan's second economic center and a manufacturing hub, Osaka shares business hours with Tokyo.