Timestamp Converter

What is a Unix Timestamp?

A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since 1 January 1970 at 00:00:00 UTC. This date is known as the Unix epoch. Timestamps are used extensively in computing because they provide a single, unambiguous number to represent any point in time, regardless of time zone or locale.

How Does This Converter Work?

This tool converts between Unix timestamps and human-readable dates in both directions. Enter a numeric timestamp (in seconds or milliseconds) and the converter will display the corresponding date in your local time zone, in UTC, and in ISO 8601 format. Alternatively, select a date and time using the date picker to get the equivalent Unix timestamp in both seconds and milliseconds. The tool automatically detects whether your input is in seconds or milliseconds based on the size of the number.

When Do You Need a Timestamp Converter?

Unix timestamps appear in server logs, API responses, database records, JWT tokens, and file metadata. Developers frequently need to convert these numbers into readable dates for debugging, auditing, or data analysis. Conversely, building API requests or setting expiry times often requires converting a specific date back into a timestamp. This converter handles both tasks instantly in your browser, with no data sent to any server.

Seconds vs Milliseconds

Most Unix systems use seconds since the epoch, producing a 10-digit number for current dates. JavaScript, Java, and some APIs use milliseconds instead, resulting in a 13-digit number. This tool supports both formats and displays results in both units, so you never have to worry about which convention a particular system uses. All processing runs entirely in your browser using standard JavaScript Date methods.