Paste a 10-digit epoch in seconds or a 13-digit millisecond timestamp and see the same moment across time zones.
Never paste production passwords, live JWT access tokens or private customer records.
No uploads, cookies, tracking or third-party scripts. Your input stays in browser memory.
Ready. Enter a test value.
APIs, log lines, JSON responses and JavaScript Date values use different timestamp units. Confusing seconds and milliseconds changes a date by decades. The converter displays the detected unit, ISO UTC date, both integer epochs and human readable timezone versions.
Enter an integer epoch and choose Auto, Seconds or Milliseconds. Auto uses magnitude rather than digit count and can guess wrong for historical or unusual dates: use an explicit unit when known. Alternatively enter a full ISO timestamp with Z or an explicit offset.
Conversion is deterministic but your device's clock/timezone and origin system's date semantics may differ. Epoch ranges outside JavaScript Date are rejected. DST gaps, historical calendars and server-side time libraries require additional verification.
A 10-digit contemporary epoch usually represents seconds; 13-digit values usually represent milliseconds. This is only a convention, so choose the unit explicitly for ambiguous input.
Yes. It shows absolute ISO UTC plus Korean standard time and a selected zone.
For converting ISO to epoch, no. Provide Z or an explicit offset such as +09:00 to avoid guessing which instant you intended.