Paste any epoch — the unit is detected, and you get UTC, your zone and anywhere else at once.
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A Unix timestamp is just the number of seconds since 1 January 1970 UTC — simple until you meet one in the wild and have to work out whether it is seconds, milliseconds or microseconds, and which timezone it should be read in. This converter detects the unit from the digit count, tells you which one it chose, and renders the moment in UTC, your own zone and any third zone side by side. It converts both ways: paste a date and get the epoch back.
10 digits = seconds — the classic epoch, what databases, cron and most APIs mean. 13 digits = milliseconds — what JavaScript's Date.now() hands you. 16 digits = microseconds, common in Python and in tracing systems. Feed a millisecond value to something expecting seconds and your record lands in the year 55,000; do it the other way and everything happened in January 1970. Both are among the most common bugs in the trade, and both are instantly visible here.
Because a timestamp has no timezone. It is one single moment on the planet; the calendar date only exists once you decide where you're standing. At 01:00 UTC it is already tomorrow in Kyiv and still yesterday in New York — same number, three different dates. That is why this tool always shows UTC next to your local zone rather than picking one and hoping. It also flags the 2038 problem: systems storing the epoch in a signed 32-bit integer run out of room on 19 January 2038 and wrap back to 1901.
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