Unix Timestamp Converter

What a Unix timestamp actually is

A Unix timestamp is just a count of seconds since midnight UTC on January 1, 1970 — a moment programmers call "the epoch." So 1700000000 isn't random; it's roughly 1.7 billion seconds after that starting point, which lands on November 14, 2023. Because it's a single number with no time zone baked in, it's how databases, log files, APIs, and JWT tokens store time under the hood. This tool turns that raw number into a date you can read, and turns a date back into the number.

Seconds vs. milliseconds — the gotcha

The number one source of confusion is length. Classic Unix time is in seconds (10 digits today, like 1719705600). JavaScript's Date.now(), and most JSON APIs, use milliseconds (13 digits, like 1719705600000). Feed a millisecond value into a tool expecting seconds and you'll get a date in the year 56,000. A quick sanity check: any current timestamp with 13 digits is milliseconds, and 10 digits is seconds. This converter lets you pick the unit so you don't accidentally land a thousand years off.

When you'd reach for this

You're debugging a server log that prints created_at: 1719705600 and need to know if that order came in this morning or last week. Or you're testing an API and it hands back an expires field as a bare number. Or you're writing a cron-driven script and want to confirm a "run at" value points where you think. Instead of writing throwaway code, you paste the number and read the date.

How to use it

1. To decode a timestamp, paste the number into the timestamp field and choose whether it's in seconds or milliseconds.
2. Read the converted human-readable date, shown in both your local time and UTC so you can compare against server logs.
3. To go the other way, enter a calendar date and time and read off the epoch value it produces.
4. Copy the result and drop it straight into your code, query, or config file.

FAQ

Why does my date look a few hours off?

A timestamp has no time zone — it's always UTC. The offset you see is your local zone. Compare using the UTC value shown to match what a server recorded.

What's the "year 2038 problem"?

Systems storing Unix time as a signed 32-bit integer overflow on January 19, 2038. Modern 64-bit systems are fine, but you may still see it in old hardware and databases.

Does anything get sent to a server?

No. The conversion runs entirely in your browser, so nothing you type is uploaded or stored.

Is it free?

Yes, free and ad-supported.