Unix Timestamp Converter Online — Convert Epoch Time to Date
Use this Unix timestamp converter online to turn epoch seconds or milliseconds into an ISO date and local date without uploading data.
About this tool
This online Unix timestamp converter accepts a numeric epoch value, detects common seconds and milliseconds inputs, and displays both the UTC ISO representation and a date formatted in your browser time zone.
How to use
- Enter a Unix timestamp as seconds or milliseconds since the Unix epoch.
- Run the converter to create an ISO UTC date and a local date.
- Check the time zone and unit before using the result in logs, APIs or databases.
Features
- Recognizes common epoch-second and epoch-millisecond values.
- Shows a standardized ISO UTC result and local browser time.
- Runs entirely in the browser.
Common use cases
- Read timestamps from API responses and application logs.
- Compare a stored epoch value with a human-readable date.
- Investigate second-versus-millisecond conversion mistakes.
Common issues and tips
- A seconds value treated as milliseconds produces a date near 1970.
- The localized result uses the current browser time zone, while the ISO result is UTC.
Privacy
Timestamp conversion runs locally in your browser. The value you enter is not uploaded to Tools12345.
Frequently asked questions
What is a Unix timestamp?
It is a count of elapsed seconds or, in some systems, milliseconds from 1970-01-01 00:00:00 UTC.
Does the converter use seconds or milliseconds?
It detects common values: smaller epoch numbers are treated as seconds and large values as milliseconds.
Why are the ISO and local times different?
ISO output is shown in UTC, while the local result follows the time zone configured in your browser and operating system.