Question 1

What is Unix epoch time?

Accepted Answer

Unix epoch time (also called POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC. It is used by virtually all computer systems to store and compare dates in a timezone-independent way.

Question 2

How do I convert epoch time to a human-readable date?

Accepted Answer

Paste your Unix timestamp into the converter above and it will instantly show the equivalent date in UTC, ISO 8601, and your selected timezone. In most programming languages, you multiply seconds by 1000 and pass to a Date constructor: new Date(timestamp * 1000).

Question 3

What is the difference between seconds and milliseconds timestamps?

Accepted Answer

Unix timestamps in seconds are 10 digits (e.g., 1711526400), while millisecond timestamps are 13 digits (e.g., 1711526400000). JavaScript, Java, and some APIs use milliseconds. Our converter auto-detects the unit based on the number length.

Question 4

What is the Y2K38 problem?

Accepted Answer

The Year 2038 problem (Y2K38) affects 32-bit systems that store Unix time as a signed 32-bit integer. The maximum value (2,147,483,647) corresponds to January 19, 2038, 03:14:07 UTC. After that, the counter overflows and wraps to a negative number. Modern 64-bit systems are unaffected.

Question 5

Are Unix timestamps affected by timezones?

Accepted Answer

No. Unix timestamps are always in UTC. The same moment in time produces the same timestamp regardless of your location. Timezones only affect how the timestamp is displayed as a human-readable date and time.

Question 6

Can Unix timestamps be negative?

Accepted Answer

Yes. Dates before January 1, 1970 are represented by negative timestamps. For example, January 1, 1969 00:00:00 UTC is timestamp -31536000. Most modern systems support negative timestamps.

Question 7

How do I get the current Unix timestamp?

Accepted Answer

In JavaScript: Math.floor(Date.now() / 1000). In Python: import time; int(time.time()). In Bash: date +%s. You can also see the live current timestamp at the top of this converter.

Question 8

What does epoch 0 represent?

Accepted Answer

Epoch 0 is January 1, 1970, 00:00:00 UTC — the start of Unix time. This date was chosen as a convenient reference point when Unix was being developed at Bell Labs in the early 1970s.

Question 9

How do leap seconds affect Unix timestamps?

Accepted Answer

Unix time does not account for leap seconds. Each day in Unix time is exactly 86,400 seconds. When a leap second is added by international timekeeping authorities, Unix systems typically either repeat a second or use a smoothing algorithm (leap smear).

Question 10

How do I convert a date to epoch time?

Accepted Answer

Switch to 'Date → Epoch' mode in the converter above, enter your date and time, and select the timezone. The tool will instantly give you the Unix timestamp in both seconds and milliseconds. In JavaScript: Math.floor(new Date('2024-03-27').getTime() / 1000).

Epoch Converter

What Is an Epoch Converter?

How Unix Timestamps Work

Key Considerations

Frequently Asked Questions

Embed Epoch Converter

You Might Also Like