Unix Timestamp Converter

Convert Unix timestamps (seconds or milliseconds) to dates and back. Auto-detects the unit, and shows both UTC and your local timezone.

Timestamp → date

Local time
—
UTC
—
ISO 8601
—

Date → timestamp

Timestamp
—

How to use the timestamp converter

A Unix timestamp (also called an epoch timestamp) counts the seconds — or milliseconds — since midnight UTC on 1 January 1970. It is the standard way computers store and exchange time, appearing in databases, log files, JSON APIs, and authentication tokens.

The first box converts a timestamp to a human-readable date. It auto-detects the unit: a value below one trillion (1e12) is treated as seconds, while a larger value is treated as milliseconds. So 1700000000 and 1700000000000 both resolve to the same instant — 14 November 2023. The result is shown three ways: in your local timezone, in UTC, and as a strict ISO 8601 string, which is what you would paste into another system.

The second box works in the opposite direction. Enter a date or datetime — ideally in ISO format such as 2023-11-14T22:13:20Z — choose whether you want the result in seconds or milliseconds, and press Convert. The tool parses the string and returns the matching timestamp. If the string cannot be parsed, it reports a clear error rather than returning a bogus value.

Tips

  • Append Z to a datetime to mean UTC, or use an offset like +08:00.
  • Millisecond timestamps are 13 digits; second timestamps are usually 10 digits.
  • Use the Now button to fill in the current time instantly.

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