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# DateFromUnixMs

> Use the Sigma DateFromUnixMs function to convert a Unix timestamp in milliseconds to the date data type in ISO date time format.

The **DateFromUnixMs** function converts a Unix timestamp in milliseconds to the [date data type](/docs/data-types-and-formats#date) in ISO date time format.

The UNIX timestamp is the number of seconds elapsed since an absolute point in time, midnight of Jan 1, 1970 in UTC time. This is also known as the [Unix epoch](https://en.wikipedia.org/wiki/Unix_time), and represents an absolute time.

## Syntax

```
DateFromUnixMs(milliseconds)
```

Function arguments:

**milliseconds** (required) The number of milliseconds since 1970-01-01 00:00:00 UTC.

## Notes

* If **milliseconds** is `Null`, the function returns `Null`.
* If your data is in seconds or microseconds, you can use the [DateFromUnix](/docs/datefromunix) or [DateFromUnixUs](/docs/datefromunixus) functions.

## Examples

```
DateFromUnixMs(0)
```

* Returns `1970-01-01 00:00:00`.

```
DateFromUnixMs(1503724894000)
```

* Returns `2017-08-26 05:21:34`.

```
DateFromUnixMs(-100000000000)
```

* Returns `1966-10-31 06:13:20`.

## Related resources

* [DateFromUnixUs](/docs/datefromunixus)
* [DateFromUnix](/docs/datefromunix)
* [Date](/docs/date)
* <a href="https://quickstarts.sigmacomputing.com/guide/common_date_functions/index.html" target="_blank" rel="noopener noreferrer">
    Quickstart: Common date functions and use cases
  </a>