Unix Timestamp Converter

A Unix timestamp is the number of seconds that have elapsed since the Unix epoch — January 1, 1970 00:00:00 UTC — not counting leap seconds. It is stored and exchanged as a single integer, which makes it timezone-independent and trivially comparable: a larger timestamp always means a later moment. Because it is just a number, it is the standard way computers and APIs exchange dates, from database records to JSON payloads and cache keys.

It depends on the unit. 10-digit values are seconds — the classic Unix timestamp, which passed 1,000,000,000 in September 2001, with the next 10-digit rollover happening in November 2286. 13-digit values are milliseconds — the unit JavaScript’s Date.getTime() and most modern APIs use. Some systems store microseconds (16 digits) or nanoseconds (19 digits), especially in Java and Go backends. This converter detects the unit automatically from the digit count, so you can paste any of them without knowing which one it is.

Unix timestamps stored as 32-bit signed integers overflow on January 19, 2038 at 03:14:07 UTC — the maximum value of a 32-bit signed integer (2,147,483,647). Systems still using 32-bit time arithmetic will wrap to 1901. Modern platforms (64-bit integers, JavaScript numbers, Python 3) are unaffected, but legacy embedded systems, old filesystems, and some databases still need patching. If you ever see a date of December 13, 1901 or January 19, 2038, a 32-bit overflow is the usual suspect.

No — a Unix timestamp is an absolute instant in time, identical everywhere on Earth. The same number means the same moment in Tokyo, London, and New York. Timezones only matter when you convert that instant into a human-readable clock time. This tool shows the instant in UTC, your local timezone, and any major city via the timezone selector, so you can compare what the same timestamp looks like around the world.

A date of January 1, 1970 00:00:00 UTC means the timestamp is 0 (or a tiny value like 1–999 that the tool reads as milliseconds). This usually happens when a value is already in seconds but your code multiplies it by 1000 again, or vice versa — a classic unit mix-up. If the year shown is 1970 and you expected a recent date, your value is in the wrong unit or has been truncated; try the other unit in the format cards to confirm.

In JavaScript: Math.floor(Date.now() / 1000) gives seconds, Date.now() gives milliseconds. In Python: int(time.time()) for seconds, int(time.time() * 1000) for milliseconds. In SQL (PostgreSQL/MySQL): EXTRACT(EPOCH FROM NOW()) or UNIX_TIMESTAMP(). In bash: date +%s. This tool’s Now button does the same job in your browser — handy when you need a reference value quickly without opening a terminal.

Multiply or divide by 1000. Seconds → milliseconds: multiply by 1000 (e.g., 1,700,000,000 s = 1,700,000,000,000 ms). Milliseconds → seconds: divide by 1000 and truncate (e.g., 1,700,000,000,000 ms = 1,700,000,000 s). Microseconds are ×1,000 from milliseconds and nanoseconds ×1,000,000. The format cards show the same instant in all four units at once, so you can grab whichever one your API expects — and the copy button always copies the plain digits, safe to paste into code.

Yes — completely free, no registration, and 100% private. All conversion happens locally in your browser with plain JavaScript; your timestamps and dates are never sent to any server. The tool works offline after the page loads. Pair it with our base64 encoder, JSON formatter, and hash generator for a complete developer toolkit.