What is a Unix timestamp?

A Unix timestamp is the number of seconds that have elapsed since 1 January 1970 00:00:00 UTC (the Unix epoch). It's a timezone-independent way to represent a point in time.

Does this tool handle millisecond timestamps?

Yes. If your value is 13 digits long (i.e. looks like a millisecond timestamp), the tool auto-detects it and converts accordingly.

Is my date data sent anywhere?

No. Conversion happens entirely in your browser using JavaScript's native Date object. Nothing is uploaded.

What's the difference between local and UTC?

UTC is the global reference time (Coordinated Universal Time). Local time is what your device clock shows, adjusted for your timezone and daylight saving.

Can I copy the ISO 8601 string?

Yes — every output field has a copy button. ISO 8601 strings look like 2024-01-15T12:30:00.000Z and are widely used in APIs.

Unix Timestamp Converter

Convert Unix timestamps to dates and back — live, two-way, private.

100% private — no uploads Date & Time ToolsFree & unlimited Read tutorial

See how it works

Watch a quick simulation of this tool in action — no file needed.

How to use Unix Timestamp Converter

Follow these steps — everything happens instantly in your browser.

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Step 1. Watch the live current Unix timestamp tick at the top of the tool.
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Step 2. Type a timestamp into the top field — the date, UTC and ISO 8601 update instantly.
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Step 3. Or pick a local date and time in the bottom field to get the matching timestamp.
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Step 4. Use “Use now” to snap both fields to the current moment, or copy any value with one click.