Unix Timestamp Converter

Convert a Unix epoch timestamp to a readable date in both UTC and your local time, or turn a date into a timestamp. Seconds and milliseconds are auto-detected, and the current time is one click away.

Enter a timestamp or date and press Convert.

What Unix time is

A Unix timestamp (epoch time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970, the "Unix epoch", not counting leap seconds. It's a single integer that represents an exact instant, independent of time zone:

date = epoch + timestamp seconds (in UTC)

Because it's just a number, it's the standard way computers store and exchange points in time. To show it to a person, you convert it to a calendar date — in UTC for an absolute reference, or in the viewer's local zone for everyday display.

Worked example

The timestamp 1700000000:

Read as seconds since 1 Jan 1970 UTC.
UTC: Tue, 14 Nov 2023, 22:13:20.
Local: the same instant shown in your own time zone.

Seconds vs milliseconds

Unix timestamps come in two scales: seconds (10 digits for current dates) used by most APIs and databases, and milliseconds (13 digits) used by JavaScript's Date.now(). This converter auto-detects which you pasted by its length, so a 13-digit value is treated as milliseconds. The well-known "Year 2038 problem" affects systems that store the timestamp in a signed 32-bit integer, which overflows in January 2038 — modern 64-bit systems are unaffected.

Tip: need to know the gap between two calendar dates instead? Use the date difference calculator.

Frequently asked questions

What is a Unix timestamp?

It's the number of seconds since midnight UTC on 1 January 1970. It represents an exact moment in time as a single integer, regardless of time zone, which is why computers use it to store dates.

Does it use seconds or milliseconds?

Both. APIs usually use seconds (10 digits today) while JavaScript uses milliseconds (13 digits). The converter detects which you entered by its length and handles either.

Why show UTC and local time?

UTC gives an absolute, time-zone-independent reference, while local time is what a person in your region actually sees. Showing both avoids confusion about which zone a date is in.

What's the Year 2038 problem?

Systems that store the timestamp in a signed 32-bit integer can only count to January 2038 before overflowing. Modern 64-bit systems use a larger integer and aren't affected.

MB
Mustafa Bilgic · Editor, Calcool
Unix time counts seconds since 1970-01-01 UTC (excluding leap seconds), the standard POSIX epoch. Conversion uses the browser's Date object. Everything runs in your browser — nothing you enter is uploaded, logged or stored.

Related calculators

📅 Date Difference Calculator🎂 Age Calculator⏱️ Hours Calculator🧩 JSON Formatter