What's Unix Epoch time?

The number of seconds (or milliseconds, in some APIs) since midnight UTC on January 1, 1970. It is the standard way computers represent a point in time, language-agnostic, time-zone-free, easy to compare and do arithmetic on.

How does the tool know if my number is seconds or milliseconds?

By a threshold check. If the number is larger than 100,000,000,000 (about year 5138 in seconds, but only ~1973 in milliseconds), it is treated as milliseconds. Below, as seconds. Works for any time after 1973 and before ~5138. Outside that range you may need to pick the unit manually in your own code.

My converted date shows the wrong time zone. Why?

The tool displays three views: ISO (UTC), UTC string, and your browser's local time. The conversion math is identical, the only difference is which timezone formatting is applied. Pick the line that matches your context.

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

Pick `Timestamp → Date`, paste the number and hit Convert: the result shows the date as ISO 8601 (UTC), as a UTC string and in your browser's local time. In code, multiply seconds by 1000 for JavaScript's `Date`, or use `datetime.fromtimestamp()` in Python (examples above).

How do I convert a date to epoch time?

Pick `Date → Timestamp`, enter the date in any format JavaScript's `Date` accepts (for example `2023-11-14T22:13:20Z`) and hit Convert: the result shows the epoch time in seconds and in milliseconds. A date and time without a time zone is read as your local time (add `Z` for UTC); a date alone, like `2023-11-14`, is read as midnight UTC.

What's the 'Year 2038 Problem'?

32-bit signed integers overflow at 2,147,483,647 seconds past the epoch, which is 03:14:08 UTC on January 19, 2038. Old systems using 32-bit `time_t` will wrap around to negative numbers (looking like 1901). Modern 64-bit systems push the limit out to ~292 billion years, so the problem mainly affects legacy embedded hardware that has not been updated.

Where is the conversion done?

Entirely in your browser via JavaScript's built-in `Date` object. Nothing leaves your device.

Free, no signup, no rate limit. Timestamp input capped at 15 digits, date string at 100 characters.

Utility

Epoch Converter

Convert Unix Timestamp to Date

Input

Mode

Unix Timestamp

Convert an epoch (Unix) timestamp to a human-readable date, or a date back to epoch time, in seconds or milliseconds. Shows UTC and your local time.

Terminal

Console ready. Execute a command to see output...

About Epoch Converter

What is epoch time?

Epoch time, also called Unix time, is the number of seconds since January 1, 1970, 00:00:00 UTC (the "Unix Epoch"). A 10-digit value is seconds, a 13-digit value is milliseconds: this epoch converter tells them apart by size and turns either one into a human-readable date, or a date back into an epoch timestamp.

Epoch time in code

The same conversion in common languages (1700000000 is 14 November 2023, 22:13:20 UTC):

JavaScript  Math.floor(Date.now() / 1000)                    // current epoch, seconds
            new Date(1700000000 * 1000).toISOString()        // "2023-11-14T22:13:20.000Z"
Python      int(time.time())                                 # current epoch, seconds
            datetime.fromtimestamp(1700000000, tz=timezone.utc)
Bash        date +%s                                         # current epoch, seconds
            date -u -d @1700000000                           # GNU date; macOS: date -u -r 1700000000
Excel       =A1/86400+DATE(1970,1,1)                         # A1 = seconds; format the cell as date/time (UTC)

The Year 2038 Problem

32-bit systems will run out of seconds on January 19, 2038. It is often called the next "Y2K". Most modern systems (64-bit) are already safe until the universe likely ends.

How to use Epoch Converter

Pick the mode
Timestamp → Date if you have a number, Date → Timestamp if you have a date string.
Enter the value
Timestamp: digits only (seconds or milliseconds). Date: any format JavaScript Date accepts (ISO 8601, short date, full string). Optional Set Local Time / Set UTC Time buttons prefill the current moment.
Hit Convert
Timestamp → Date shows ISO, UTC, and your local time. Date → Timestamp shows both seconds and milliseconds.
Copy what you need
Each line is selectable in the terminal panel. Match the format your downstream system expects.

Frequently Asked Questions

: The number of seconds (or milliseconds, in some APIs) since midnight UTC on January 1, 1970. It is the standard way computers represent a point in time, language-agnostic, time-zone-free, easy to compare and do arithmetic on.
: By a threshold check. If the number is larger than 100,000,000,000 (about year 5138 in seconds, but only ~1973 in milliseconds), it is treated as milliseconds. Below, as seconds. Works for any time after 1973 and before ~5138. Outside that range you may need to pick the unit manually in your own code.
: The tool displays three views: ISO (UTC), UTC string, and your browser's local time. The conversion math is identical, the only difference is which timezone formatting is applied. Pick the line that matches your context.
: Pick Timestamp → Date, paste the number and hit Convert: the result shows the date as ISO 8601 (UTC), as a UTC string and in your browser's local time. In code, multiply seconds by 1000 for JavaScript's Date, or use datetime.fromtimestamp() in Python (examples above).
: Pick Date → Timestamp, enter the date in any format JavaScript's Date accepts (for example 2023-11-14T22:13:20Z) and hit Convert: the result shows the epoch time in seconds and in milliseconds. A date and time without a time zone is read as your local time (add Z for UTC); a date alone, like 2023-11-14, is read as midnight UTC.
: 32-bit signed integers overflow at 2,147,483,647 seconds past the epoch, which is 03:14:08 UTC on January 19, 2038. Old systems using 32-bit time_t will wrap around to negative numbers (looking like 1901). Modern 64-bit systems push the limit out to ~292 billion years, so the problem mainly affects legacy embedded hardware that has not been updated.
: Entirely in your browser via JavaScript's built-in Date object. Nothing leaves your device.
: Free, no signup, no rate limit. Timestamp input capped at 15 digits, date string at 100 characters.