Does it account for Daylight Saving Time?

Yes, our converter uses the IANA timezone database, which includes all current DST rules for every timezone in the world.

UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks. All timezones are defined as offsets from UTC.

Can I compare multiple timezones at once?

Yes, you can add multiple cities or timezones and see the equivalent times side by side.

How many timezones are there in the world?

There are 38 distinct UTC offsets in use, ranging from UTC-12 to UTC+14. This includes half-hour (UTC+5:30 India, UTC+9:30 Australia) and 45-minute offsets (UTC+5:45 Nepal, UTC+8:45 Australia).

What is the International Date Line?

The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean. When you cross it westward, you gain a day; crossing eastward, you lose a day.

Why do some timezones have 30 or 45 minute offsets?

Countries chose offsets that best matched their solar noon. India uses UTC+5:30 and Nepal uses UTC+5:45 because standard hourly offsets didn't align well with their geography.

Which country has the most timezones?

France has the most (12 timezones) due to overseas territories. Russia spans 11 timezones. The US has 6 (including Hawaii and Alaska).

Sri Lanka to MST

-12h 30m

Sri Lanka

ISTSOURCE

UTC+05:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

MST

UTC-06:00☀ DST active

HH11

MM30

(previous day)23:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Sri Lanka

MST

12:00 AM

12:30 PM-1

2:00 AM

2:30 PM-1

4:00 AM

4:30 PM-1

6:00 AM

6:30 PM-1

8:00 AM

8:30 PM-1

10:00 AM

10:30 PM-1

12:00 PM

12:30 AM

2:00 PM

2:30 AM

4:00 PM

4:30 AM

6:00 PM

6:30 AM

8:00 PM

8:30 AM

10:00 PM

10:30 AM

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

IST and MST on the World Map

The map below highlights the IST (India Standard Time) and MST (Mountain Standard Time) timezone regions across the globe.

IST Zone

→

MST Zone

Explore all world timezones interactively →

IST – India Standard Time

UTC+05:30

India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.

Countries in IST

IndiaSri Lanka

Major Cities in IST

MumbaiDelhiBangaloreKolkataChennaiHyderabadPuneAhmedabadColomboJaipurLucknowSurat

Key Facts about IST

•India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
•India uses a single time zone despite spanning 30° of longitude.
•IST is one of only a handful of time zones with a 30-minute offset.
•IST is the most populous single time zone in the world with over 1.4 billion people.
•The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.

Daylight Saving:No – UTC+05:30 year-round

Learn more about IST on Wikipedia

MST – Mountain Standard Time

UTC-07:00

Mountain Standard Time (MST) is the time zone for the Mountain region of North America, 7 hours behind UTC.

Countries in MST

United States (Mountain)Canada (Alberta)Mexico (Chihuahua, Sonora)

Major Cities in MST

DenverPhoenixSalt Lake CityCalgaryEdmontonAlbuquerqueEl PasoTucsonBoiseCiudad Juárez

Key Facts about MST

•Arizona does not observe daylight saving time, staying on MST year-round.
•The Navajo Nation in Arizona does observe DST, unlike the rest of the state.
•Denver, the 'Mile High City', is the largest city fully in MST.
•MST covers 6 US states entirely and parts of several others.

Daylight Saving:Yes – switches to MDT

Learn more about MST on Wikipedia

Sri Lanka vs MST: Offsets, DST and Best Call Times

Sri Lanka runs on India Standard Time (IST) at UTC+05:30. MST runs on Mountain Standard Time (MST) at UTC-07:00. That puts Sri Lanka 12 hours 30 minutes behind MST — a difference of -12h 30m at the current offsets.

In practice, when it is 9:00 AM in Sri Lanka it is 8:30 PM in MST on the previous day. Midnight in Sri Lanka is 11:30 AM in MST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Sri Lanka to MST time conversion table

Sri Lanka (IST)	MST (MST)	Day
12:00 AM	11:30 AM	previous day
6:00 AM	5:30 PM	previous day
7:00 AM	6:30 PM	previous day
8:00 AM	7:30 PM	previous day
9:00 AM	8:30 PM	previous day
12:00 PM	11:30 PM	previous day
3:00 PM	2:30 AM	same day
5:00 PM	4:30 AM	same day
6:00 PM	5:30 AM	same day
9:00 PM	8:30 AM	same day

Why people convert Sri Lanka to MST time

Scheduling a call from Sri Lanka to MST: a 10:00 AM start in Sri Lanka lands at 9:30 PM in MST the previous day, so you can confirm the slot without doing the arithmetic yourself.
Handling a -12h 30m gap: Sri Lanka and MST 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 MST is 8:30 PM in Sri Lanka.
Watching a live event or market open: Sri Lanka viewers need 8:30 PM in MST to catch a 9:00 AM start there, and 12:30 PM if the event is anchored to Sri Lanka.

Always state the zone abbreviation, not just the hour. "3:00 PM IST" is unambiguous; "3 PM" across a -12h 30m gap is not.
With a -12h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week Sri Lanka takes the early slot, the next week MST does.

About IST (India Standard Time)

India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.

About MST (Mountain Standard Time)

Mountain Standard Time (MST) covers the Rocky Mountain region of the United States and Canada. Arizona is notable for not observing daylight saving time, staying on MST year-round (except the Navajo Nation). The time zone includes major cities like Denver, Phoenix, Calgary, and Salt Lake City. During summer, most areas switch to Mountain Daylight Time (MDT, UTC-06:00).

Best time to call between Sri Lanka and MST

With a -12h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. MST opens at 9:00 AM MST, which is 8:30 PM in Sri Lanka, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Sri Lanka and MST have no shared working hours because of the -12h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.

Sri Lanka is 12 hours 30 minutes behind MST (IST UTC+05:30 → MST UTC-07:00). 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

Sri Lanka

Does not observe DST

MST

☀ 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 Sri Lanka and MST?

Sri Lanka (IST, UTC+05:30) is 12 hours 30 minutes behind MST (MST, UTC-07:00). The gap is currently -12h 30m.

How do I convert Sri Lanka time to MST time?

Add -12h 30m to Sri Lanka local time. For example, 9:00 AM in Sri Lanka is 8:30 PM in MST (previous day).

What time is it in MST right now?

MST uses MST at UTC-07:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -12h 30m offset from Sri Lanka.

What is the best time to call MST from Sri Lanka?

There is no shared working-hours window because of the -12h 30m gap. The closest option is 1:00 PM in Sri Lanka, which is 12:30 AM in MST.

Which is behind, Sri Lanka or MST?

Sri Lanka is 12 hours 30 minutes behind MST. When it is 12:00 PM in Sri Lanka it is 11:30 PM in MST.

Do Sri Lanka and MST use different time zones?

Sri Lanka (Sri Lanka) uses IST at UTC+05:30, while MST uses MST at UTC-07:00. The IANA identifiers are Asia/Colombo and America/Denver.

Does daylight saving time affect the Sri Lanka–MST difference?

Neither zone observes daylight saving time, so the -12h 30m offset between Sri Lanka and MST is fixed all year.

Which other cities share Sri Lanka's time zone?

IST also covers Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad and 4 more.

Which countries use IST, Sri Lanka's zone?

IST is used in India, Sri Lanka.

Is there a day difference between Sri Lanka and MST?

Sometimes. The -12h 30m gap is large enough that 8:00 PM or later in Sri Lanka already falls on the in MST.

What is the time difference between Sri Lanka and MST?

MST is -12h 30m from Sri Lanka.

What timezone is Sri Lanka in?

Sri Lanka operates on its local timezone.

What timezone is MST in?

MST operates on its local timezone.

Which countries use IST (India Standard Time)?

IST is used in India, Sri Lanka.

Does IST observe daylight saving time?

No, IST does not observe daylight saving time and remains at UTC+05:30 year-round.

What are some interesting facts about IST?

India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT. India uses a single time zone despite spanning 30° of longitude.

Which cities are in the MST timezone?

Major cities in the MST timezone include Denver, Phoenix, Salt Lake City, Calgary, Edmonton, Albuquerque, El Paso, Tucson.

What is the UTC offset for MST?

Mountain Standard Time (MST) is at UTC-07:00. During daylight saving time, it shifts to MDT.

What should I know about the MST timezone?

Arizona does not observe daylight saving time, staying on MST year-round. The Navajo Nation in Arizona does observe DST, unlike the rest of the state.