How do I know if my timestamp is in seconds or milliseconds?

A 10-digit number is almost certainly seconds. A 13-digit number is milliseconds. For example, 1700000000 is seconds (November 2023) while 1700000000000 is milliseconds representing the same moment.

What is the maximum Unix timestamp?

32-bit signed integers can hold timestamps up to 2147483647 (19 January 2038), the so-called Year 2038 problem. JavaScript uses 64-bit floats so this tool handles timestamps far beyond that date.

Timestamp Converter — Unix Timestamp to Date

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Current Unix timestamp (seconds)

Unix timestamp → human date

Date / time → Unix timestamp

About the Timestamp Converter

Unix timestamps appear everywhere in software: API responses, database records, log files, and JWT tokens. This converter lets you instantly translate between a Unix timestamp and a human-readable date/time, and vice versa.

Seconds vs milliseconds

Most systems use seconds (10 digits), but JavaScript and many modern APIs use milliseconds (13 digits). Select the correct unit before converting.

Relative time

The converter also shows how long ago (or in the future) the timestamp is — useful when reading log files or API responses.

Frequently Asked Questions

What is a Unix timestamp?

Seconds elapsed since 1 January 1970 00:00:00 UTC. Used universally in programming, APIs, and databases.

Seconds or milliseconds?

10 digits = seconds. 13 digits = milliseconds. Select the right unit in the dropdown.

What is the year 2038 problem?

32-bit systems can only store timestamps up to 19 January 2038. This tool uses JavaScript 64-bit floats so handles dates far beyond that.

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