EDT to MDT Converter

Convert time between Eastern Daylight Time (EDT) and Mountain Daylight Time (MDT)

Eastern Daylight Time (EDT)

07:00:34
UTC +0
Dec 07, 2025
America/New_York

Mountain Daylight Time (MDT)

07:00:34
UTC +0
Dec 07, 2025
America/Denver

Time Difference

Mountain Daylight Time (MDT) is 0 hours ahead of Eastern Daylight Time (EDT)

Select Date

Select Time

Quick Reference

EDTMDT
21:0019:00
23:0021:00
01:0023:00
03:0001:00
05:0003:00
07:0005:00
09:0007:00
11:0009:00
13:0011:00
15:0013:00
17:0015:00
19:0017:00

Top 10 Most Common Time Zones

AbbreviationFull NameUTC OffsetTypical Use
UTCCoordinated Universal TimeUTC ±0Global reference standard (servers, logs, APIs)
EST / EDTEastern (US) TimeUTC −5 / −4New York, Toronto — North American business hub
CST / CDTCentral (US) TimeUTC −6 / −5Chicago, Dallas — US central business region
PST / PDTPacific (US) TimeUTC −8 / −7San Francisco, Los Angeles — tech industry standard
GMT / BSTGreenwich Mean / British Summer TimeUTC 0 / +1UK, used globally as a reference with UTC
CET / CESTCentral European (Summer) TimeUTC +1 / +2Paris, Berlin, Amsterdam — EU business core
ISTIndia Standard TimeUTC +5:30India — major IT & outsourcing region
CSTChina Standard TimeUTC +8Beijing, Shanghai — East Asia business hub
JSTJapan Standard TimeUTC +9Tokyo — finance & tech hub
AEST / AEDTAustralian Eastern (Daylight) TimeUTC +10 / +11Sydney, Melbourne — APAC regional business

Why Time Zone Abbreviations Are Ambiguous

Unlike standardized identifiers (like America/New_York or Europe/London from the IANA tz database), abbreviations such as "CST" or "IST" are not globally unique. They can refer to different time zones depending on context — country, region, or even time of year (due to daylight saving time).

Common Ambiguous Time Zone Abbreviations

Abbrev.Common Meaning(s)UTC OffsetRegion(s)
CSTCentral Standard Time / China Standard Time / Cuba Standard TimeUTC−6 / UTC+8 / UTC−5North America, China, Cuba
ISTIndian Standard Time / Irish Standard Time / Israel Standard TimeUTC+5:30 / UTC+1 / UTC+2India, Ireland, Israel
ASTAtlantic Standard Time / Arabia Standard TimeUTC−4 / UTC+3Caribbean, Canada, Middle East
PSTPacific Standard Time / Philippine Standard TimeUTC−8 / UTC+8North America, Philippines
ESTEastern Standard Time (North America / Australia)UTC−5 / UTC+10North America, Australia

✅ Best Practice

To avoid ambiguity, always:

  • Use IANA tz identifiers — e.g., America/New_York instead of "EST"
  • Specify UTC offset explicitly — e.g., UTC−5 when abbreviations must be used
  • Include the full timezone name — e.g., "Eastern Standard Time (EST)" with UTC offset

About EDT to MDT Time Conversion

Converting time between Eastern Daylight Time (EDT) and Mountain Daylight Time (MDT) is essential for coordinating between the East Coast and Mountain regions during summer months. Both EDT and MDT observe daylight saving time (March to November), making this a consistent 2-hour difference during the entire daylight saving period. EDT is UTC-4 while MDT is UTC-6, making MDT exactly 2 hours behind EDT.

This converter is valuable for business operations, travel planning, and personal coordination between Eastern seaboard cities (New York, Boston, Philadelphia) and Mountain region locations (Denver, Salt Lake City, Colorado Springs). The 2-hour difference creates favorable overlap for business coordination, unlike the 3-hour EDT-PDT or EDT-PST differences.

Common Use Cases for EDT to MDT Conversion

Business & Work

  • Scheduling meetings between East Coast offices and Mountain region headquarters
  • Coordinating between New York and Denver corporate operations
  • Planning conference calls and webinars across East-to-Mountain regions
  • Managing distributed teams during summer daylight saving months
  • Coordinating summer project deadlines and deliverables

Personal & Travel

  • Planning summer travel between Eastern and Mountain states
  • Coordinating with family and friends during vacation periods
  • Scheduling outdoor events and activities across regions
  • Managing time-sensitive summer appointments
  • Understanding local times in Mountain region vacation destinations

Time Zone Information

Eastern Daylight Time (EDT)

  • UTC Offset: UTC-4 (UTC-5 during EST)
  • IANA Timezone: America/New_York
  • Daylight Saving: Second Sunday in March to First Sunday in November
  • Major Cities: New York, Boston, Philadelphia, Atlanta, Miami, Washington DC
  • Coverage: Eastern United States and Canada

Mountain Daylight Time (MDT)

  • UTC Offset: UTC-6 (UTC-7 during MST)
  • IANA Timezone: America/Denver
  • Daylight Saving: Second Sunday in March to First Sunday in November
  • Major Cities: Denver, Salt Lake City, Colorado Springs, Albuquerque, Boise
  • Coverage: Mountain United States and Canada

Quick Reference: EDT to MDT

8:00 AM EDT
6:00 AM MDT
12:00 PM EDT
10:00 AM MDT
5:00 PM EDT
3:00 PM MDT
9:00 PM EDT
7:00 PM MDT

Remember: MDT is always 2 hours behind EDT. Both regions observe daylight saving time from March to November

Frequently Asked Questions

What is the time difference between EDT and MDT?

Eastern Daylight Time (EDT) is UTC-4, while Mountain Daylight Time (MDT) is UTC-6. This means EDT is 2 hours ahead of MDT. When it's 12:00 PM in New York (EDT), it's 10:00 AM in Denver (MDT).

Why is EDT to MDT more favorable than EDT to PDT?

EDT to MDT has only a 2-hour difference (compared to 3-hour for PDT), creating better business coordination windows. A meeting at 10 AM EDT (8 AM MDT) is reasonable for both coasts, whereas EDT to PDT requires 9 AM EDT (6 AM PDT) meetings which are too early for West Coast offices.

When are EDT and MDT active?

Both EDT and MDT are active during the same period: from the second Sunday in March through the first Sunday in November. This makes the 2-hour difference consistent throughout the entire daylight saving time period, unlike EDT-MST which changes seasonally.

What are the best times to schedule calls between EDT and MDT zones?

Optimal meeting windows: 8-10 AM EDT (6-8 AM MDT), 10 AM-12 PM EDT (8-10 AM MDT), 2-4 PM EDT (12-2 PM MDT), and 4-5 PM EDT (2-3 PM MDT). The sweet spot is 10 AM-12 PM EDT (8-10 AM MDT) when both regions are in productive morning hours.

Why coordinate between EDT and MDT regions?

Major coordination reasons: tech companies with offices in both regions, national corporations with Eastern headquarters and Mountain distribution centers, entertainment/media production spanning coasts, retail chains coordinating operations, and summer travel/event planning between states.

How do EDT and MDT transitions affect scheduling?

EDT and MDT transition on the exact same dates (second Sunday in March and first Sunday in November), so the 2-hour difference remains consistent year-round during their active periods. You don't need to adjust for transition timing changes like you would with EDT-MST or EDT-PST comparisons.

Pro Tips

  • • Use "10 AM ET / 8 AM MT" format when scheduling calls - this double notation prevents timezone confusion and helps both teams understand exact timing.
  • • The 2-hour difference is ideal for summer coordination. A 10 AM EDT meeting is 8 AM MDT - early but reasonable, avoiding the extreme early mornings of EDT-PDT.
  • • Best productivity window: 10 AM-12 PM EDT (8-10 AM MDT) gets both regions engaged without sacrificing work-life balance for either side.
  • • Plan summer projects and events using the EDT-MDT window - the consistent 2-hour difference throughout summer months makes planning easier.
  • • Both regions transition on the same dates (March and November), so maintain the same meeting time slots year-round without adjustment.
  • • For Mountain region teams, schedule recurring meetings before 9 AM MDT (11 AM EDT) to avoid afternoon fatigue; for EDT teams, schedule before 5 PM EDT (3 PM MDT).

Update Logs

View the latest updates and features