Time Zone Conversion Guide: Never Miss a Meeting Again

The time zone math is simpler than you think

When someone tells you "the meeting is at 2 PM Pacific time," you need a fast way to figure out what that means where you are. The core concept is straightforward: each time zone is a fixed number of hours ahead of or behind UTC (Coordinated Universal Time), the global standard.

Once you know the UTC offset for your time zone and theirs, it's just addition or subtraction.

Quick reference: major time zones in the US

These are the standard (winter) offsets. During daylight saving time, most shift one hour ahead:

• Eastern Time (ET): UTC-5 (EST) or UTC-4 (EDT)
• Central Time (CT): UTC-6 (CST) or UTC-5 (CDT)
• Mountain Time (MT): UTC-7 (MST) or UTC-6 (MDT)
• Pacific Time (PT): UTC-8 (PST) or UTC-7 (PDT)

The E, C, M, and P times are 1 hour apart from each other, so figuring out the time in a different US zone is just counting hours.

Converting between US time zones: worked example

Your team call is at 2 PM Pacific Time. You're in Eastern Time. How far ahead is Eastern from Pacific?

Eastern is 3 hours ahead of Pacific (5 hours behind UTC vs. 8 hours behind UTC). So 2 PM PT = 5 PM ET.

Another way: go through UTC. 2 PM Pacific is 2 PM + 8 hours = 10 PM UTC. Then 10 PM UTC - 5 hours = 5 PM ET. Same answer, different path.

Daylight saving time makes it tricky

Most US time zones shift forward one hour in March and back one hour in October. But not all regions observe it parts of Arizona, Hawaii, and US territories stay on standard time year-round. During the transition weeks when one state has switched and another hasn't, offsets shift. This is why manually calculating can fail.

For international calls, it gets worse: not every country switches on the same date, so the US-to-UK offset shifts three times a year.

When to use a converter instead of doing the math

Knowing the concept is valuable it helps you catch errors and understand why scheduling is hard. But for anything important, use a tool. You avoid off-by-one mistakes, and you don't have to look up which zones observe daylight saving time or when the transitions happen.