Unix Timestamp Converter
Convert a Unix timestamp (seconds or milliseconds) to a readable date in UTC, ISO 8601 and local time — and convert any date back to a timestamp. Live current epoch time.
Timestamp → date
Date → timestamp
The date above is read in your browser’s local time zone (UTC).
Unix time, explained: seconds since 1970
A Unix timestamp is a single integer: the number of seconds since the "epoch", 00:00:00 UTC on 1 January 1970. Because it carries no timezone and no formatting, it is unambiguous — two systems anywhere in the world agree on exactly which instant a given timestamp refers to. That is why it is the default way to store and transmit time in databases, log files, JWT claims, HTTP headers and most APIs.
The main source of confusion is scale. Classic Unix tooling and most backend languages count whole seconds, so a current timestamp is a 10-digit number. JavaScript (Date.now()), Java (System.currentTimeMillis()) and many browser APIs count milliseconds, giving 13 digits. Some systems go further to microseconds or nanoseconds. This converter assumes values with 13 or more digits are milliseconds and shorter values are seconds, and lets you override that guess.
Converting to a human date always involves a timezone. The same timestamp is "2023-11-14T22:13:20Z" in UTC and, say, "2:13 PM PST" on the US west coast — one instant, two labels. The ISO 8601 output here ends in "Z" to make the UTC basis explicit; the "Local" line applies your browser’s current timezone and daylight-saving offset.
Unix time deliberately ignores leap seconds: every day is treated as exactly 86,400 seconds. This keeps the arithmetic reversible at the cost of being a few seconds out of step with astronomical time. For almost all software that is the right trade-off. The historical "year 2038 problem" affects only systems that store the value in a signed 32-bit integer; 64-bit storage pushes the overflow far beyond any practical horizon.
Everything on this page runs locally through the browser’s built-in Date and Intl APIs, so you can convert timestamps offline and nothing you enter is sent anywhere.
Key formulas (reference)
timestamp (seconds) → date: new Date(ts * 1000) timestamp (milliseconds) → date: new Date(ts) date → timestamp (seconds): Math.floor(date.getTime() / 1000) ISO 8601 UTC: date.toISOString() // e.g. 2023-11-14T22:13:20.000Z
Related tools
These free tools pair well with this page — open them in a new tab to finish your workflow.
Frequently Asked Questions
What is a Unix timestamp?
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970, not counting leap seconds. It is a timezone-independent way to represent a single moment, which is why it is used throughout databases, APIs and log files.
Is the timestamp in seconds or milliseconds?
Both are common. Unix tools and most backend systems use seconds (a 10-digit number for current dates). JavaScript’s Date.now() and many web APIs use milliseconds (13 digits). This converter auto-detects based on magnitude — numbers of 13 or more digits are treated as milliseconds — and you can force either interpretation.
Why does the local time differ from the UTC time?
A timestamp is an absolute instant. "UTC" shows that instant at the zero meridian; "Local" shows the same instant adjusted to your browser’s timezone and current daylight-saving offset. They refer to the same moment, just displayed in different zones.
What is the year 2038 problem?
Systems that store the timestamp in a signed 32-bit integer overflow on 19 January 2038, when the value exceeds 2,147,483,647. Modern platforms use 64-bit integers and are unaffected for billions of years. This tool uses JavaScript numbers and handles dates far outside the 32-bit range.
Does the converter account for leap seconds?
No, and neither does Unix time itself by definition. Unix time assumes every day is exactly 86,400 seconds. Leap seconds inserted into UTC are effectively ignored, so the mapping between Unix time and UTC is simple and reversible.
Can I convert a timestamp to a specific timezone other than my own?
This tool shows UTC and your local zone. For an arbitrary target zone, take the UTC result here and use the Time Zone Converter, or compute the offset manually. The ISO 8601 output ends in "Z", meaning UTC.
Is anything sent to a server?
No. All parsing and formatting happens in your browser with the built-in Date and Intl APIs. You can use the tool offline once the page has loaded.