How to Use This Tool
A timestamp is just a count of how long it has been since midnight UTC on 1 January 1970. That single number is unambiguous, timezone-free and easy to sort, which is why it is everywhere in logs, databases and APIs. It is also completely unreadable, and the number you have been handed might be counting seconds, milliseconds or microseconds with nothing to tell you which.
Converting a timestamp
Paste the number and the tool detects the precision from its magnitude, then says so explicitly rather than guessing silently. This is the part that goes wrong most often: pass a millisecond value to something expecting seconds and you get a date roughly fifty thousand years in the future; pass seconds where milliseconds are expected and everything collapses to January 1970. Both failures show up in production logs constantly, and both are instantly obvious once the date is rendered.
The result is shown in UTC and in your browser's local timezone side by side. Read the offset carefully. A timestamp itself has no timezone — the same number is the same instant everywhere on earth. The timezone only appears when you format it for a human, which is precisely why storing local time in a database and timestamps in logs causes so much confusion during an incident.
Going the other way
Switch to Date → timestamp to convert a calendar date into an epoch value. The interpret as selector matters more than it looks: entering "2026-08-02 09:00" and treating it as local time produces a different number from treating it as UTC, by exactly your offset. When you are constructing a query filter or a test fixture, choosing the wrong one shifts your whole result set by several hours.
Formats you will actually be asked for
The list at the bottom gives ISO 8601 with and without offset, the RFC 2822 form that HTTP headers and email use, a SQL-friendly form, and a plain human sentence. Copy whichever the receiving system expects. ISO 8601 with an explicit offset is the safest default for anything crossing a system boundary, because it is unambiguous and sorts correctly as a string.