Developer Tools

Unix Timestamp Converter

Convert timestamps in seconds or milliseconds to ISO dates and time zones, or convert an ISO date back to a timestamp.

Your results

How to read log timestamps and convert dates

Use this converter to compare Unix timestamps with dates in logs or API responses. A timestamp identifies an instant; the selected timezone changes its display, not that instant.

Step by step

Choose timestamp input and select seconds or milliseconds, or switch to date input.
For a date, enter ISO 8601 with Z or an explicit offset. Use a timezone name such as Europe/Oslo for the displayed result.
Run the conversion, then copy or download the seconds, milliseconds and UTC date. Use the current-time button when needed.

Settings and limits

Seconds or milliseconds: The same instant can be expressed as 1704067200 seconds or 1704067200000 milliseconds. Select the unit explicitly instead of guessing from the digit count.
Date offset: 2024-01-01T01:00:00+01:00 equals 2024-01-01T00:00:00Z. The offset belongs to the input date, independently of the display timezone.
Display timezone: UTC is the default. Europe/Oslo displays the example as 01:00:00 on 2024-01-01; the Unix timestamp stays unchanged.

Worked example

Convert 1704067200 seconds using UTC. Expect 1704067200000 milliseconds and 2024-01-01T00:00:00.000Z.

Download the example files

timestamp-example.txt

Example input

1704067200 · UTC

Expected result

1704067200000
2024-01-01T00:00:00.000Z
Europe/Oslo: 2024-01-01 01:00:00 +01:00

Now choose Europe/Oslo: the local time is 01:00:00. Switch to date input and paste 2024-01-01T01:00:00+01:00 to recover the same timestamp.

Questions and troubleshooting

Why is the result near the Unix epoch?

A common cause is reading seconds as milliseconds. Verify the chosen unit and compare with the UTC output.

Why is my local date rejected?

Date input needs a full date and time with Z or an offset. A date without a timezone is ambiguous; impossible dates and leap seconds are rejected.

How do daylight-saving changes affect conversion?

Use the explicit offset in the source record. A repeated local clock time may identify different instants; the display timezone applies its seasonal offset.