About this unix timestamp converter
Convert Unix seconds, milliseconds, and explicit UTC timestamps. Choose the input format. Unix timestamps convert to UTC ISO text; ISO timestamps ending in Z convert to seconds and milliseconds. Use this workspace to prepare a result you can review before putting it to use. All processing takes place on your device, without an account or an upload of your inputs. Check the examples to understand the expected output, read the limitations for the supported scope, and reset the form when you want to start a separate task.
How it works
Choose the input format. Unix timestamps convert to UTC ISO text; ISO timestamps ending in Z convert to seconds and milliseconds.
Try these examples
0; seconds
1970-01-01T00:00:00.000Z
2000-01-01T00:00:00Z; iso
Unix seconds: 946684800
Limitations & privacy
Use whole-number Unix timestamps or YYYY-MM-DDTHH:mm:ss[.SSS]Z. Local time zones and leap seconds are not supported. Calendar dates and times are validated.
Inputs and results stay in this browser. Only tool identifiers are stored for your recently used tools. You can clear that history from the directory.
A few good questions
How is the result produced?
Choose the input format. Unix timestamps convert to UTC ISO text; ISO timestamps ending in Z convert to seconds and milliseconds.
Are my inputs sent to a server?
No. Inputs and results are processed locally and are not uploaded or included in telemetry. Copying or downloading is your choice.
What are the limits of this tool?
Use whole-number Unix timestamps or YYYY-MM-DDTHH:mm:ss[.SSS]Z. Local time zones and leap seconds are not supported. Calendar dates and times are validated.
Updated September 19, 2026