Unix Timestamp Converter

Convert between Unix timestamps and readable local or UTC date-time values. Processing takes place locally in your browser.

Start using

Convert in either direction. Select automatic detection, seconds or milliseconds explicitly; check the ISO UTC result and browser time zone. Clear removes the result and keeps inputs.

1000 s → 1970-01-01T00:16:40.000Z
1000 ms → 1970-01-01T00:00:01.000Z

Unix Timestamp to Date Converter

Converts a numeric Unix timestamp to a browser-local date/time, ISO UTC timestamp and UTC text. The unit can be forced to seconds or milliseconds, or selected automatically; empty and non-finite input is rejected.

Auto mode treats absolute values below 100,000,000,000 as seconds and values at or above that threshold as milliseconds. Therefore unusual early millisecond timestamps should use the explicit Milliseconds option rather than Auto.

Verified explicit/automatic seconds input 0 produces ISO 1970-01-01T00:00:00.000Z. Negative timestamps represent instants before the Unix epoch, and fractional values are accepted when they produce a valid JavaScript Date.

The local first line depends on the browser's locale and system time zone, while ISO and UTC lines describe the same instant independently of display locale. The tool does not parse formatted dates, GPS time, Excel serial dates, leap seconds or custom epochs.

Conversion happens locally and rejects values outside JavaScript Date range. For logs and integrations, retain the explicit unit and ISO value because a bare 10- or 13-digit number can otherwise be misinterpreted.

Date to Unix Timestamp Converter

Enter the local date and time, then run the conversion. Read the seconds, milliseconds, UTC ISO value and reported time-zone identifier. There is no separate time-zone selector.

You can include seconds and milliseconds. Copy sends the current result text to the clipboard. Clear removes only the result and keeps the entered date and time. There is no file download.

Processing takes place locally in your browser.

How to use

Convert in either direction. Select automatic detection, seconds or milliseconds explicitly; check the ISO UTC result and browser time zone. Clear removes the result and keeps inputs.

1000 s → 1970-01-01T00:16:40.000Z
1000 ms → 1970-01-01T00:00:01.000Z

Enter an ungrouped numeric Unix timestamp and select Auto-detect, seconds or Milliseconds. Auto uses seconds below an absolute value of 100,000,000,000 and milliseconds at or above it.
Choose Convert to Date/Time after changing the value or unit. Read the browser-local first line, ISO UTC line and UTC text line.
Copy all copies the three result lines. Clear resets the result message while retaining the input and selected unit.

Use a decimal point and no thousands separators, for example -1.5 seconds or 1.5e3 milliseconds. JavaScript Date keeps whole milliseconds; smaller fractions are truncated toward zero.

Date to Unix Timestamp Converter

Enter the local date and time, then run the conversion. Read the seconds, milliseconds, UTC ISO value and reported time-zone identifier. There is no separate time-zone selector.

You can include seconds and milliseconds. Copy sends the current result text to the clipboard. Clear removes only the result and keeps the entered date and time. There is no file download.