Date to Timestamp Converter
Convert any date and time to a Unix timestamp in seconds or milliseconds, in local time or UTC.
| Unix timestamp (seconds) | |
|---|---|
| Milliseconds | |
| ISO 8601 (UTC) | |
| ISO 8601 (with local offset) | |
| UTC date & time | |
| Local date & time | |
| Relative to now |
Bulk convert
Dates without a zone use the Interpret as setting above. Anything with an
explicit offset (Z, +02:00) keeps its own zone.
How it works
Pick a date and a time and the Unix timestamp appears instantly — in seconds (the classic
epoch value used by most APIs, databases and date +%s) and in milliseconds (what
JavaScript's Date.now() returns). The same instant is also shown as ISO 8601, as a
readable UTC string and as a readable local string, so you can double-check that you converted
the moment you meant. Use the Interpret as selector to say whether the date and
time you typed are wall-clock time in your own zone or already in UTC: this is the single
biggest source of "my timestamp is a few hours off" bugs.
The bulk box converts a whole list at once — one date per line, in any format the browser's
date parser understands (2024-03-15, 2024-03-15 10:30:00,
2024-03-15T10:30:00Z, 15 March 2024). Lines that cannot be parsed are
flagged instead of silently dropped. Everything is computed locally with the built-in
Date API: no request is made, no date you type is logged, and the page keeps
working offline.
Frequently asked questions
How do I convert a date to a Unix timestamp?
Pick the date and time, choose whether that value is local time or UTC, and the Unix timestamp appears instantly — in seconds and in milliseconds. A Unix timestamp is simply the number of seconds that have passed since 1 January 1970 at 00:00:00 UTC, so the same instant always gives the same number no matter where in the world you convert it.
What is the difference between a timestamp in seconds and in milliseconds?
Seconds is the classic Unix epoch value used by databases, APIs, JWTs and shell commands like date +%s. Milliseconds is the same instant multiplied by 1000 and is what JavaScript's Date.now() and Java's System.currentTimeMillis() return. A 10-digit number is almost always seconds and a 13-digit number is milliseconds — mixing them up puts your date in 1970 or thousands of years in the future.
Does the timestamp depend on my time zone?
The timestamp itself does not — it is always counted from an instant in UTC. What depends on your time zone is how the date and time you typed are interpreted. "15 March 2024, 10:30" is a different instant in Berlin than in New York, so use the Interpret as selector to say whether you mean your local wall clock or UTC. The tool shows both readable forms so you can confirm you converted the moment you meant.