Timestamp input
Convert a Unix timestamp into UTC, local, ISO, seconds, and milliseconds values.
UTC date to timestamp
Enter a UTC date and time to convert it back into Unix epoch values.
Unix Timestamp Converter
Convert Unix timestamps in seconds, milliseconds, or microseconds to readable UTC and local dates, then convert UTC date inputs back to epoch values.
How this Unix timestamp converter works
A Unix timestamp counts time from the Unix epoch: 1970-01-01 00:00:00 UTC. Enter a timestamp and the converter shows the UTC date, your local date, an ISO string, Unix seconds, and Unix milliseconds.
Auto-detect mode uses the number of digits before the decimal point. It treats 0 to 11 digits as seconds, 12 to 14 digits as milliseconds, and 15 or more digits as microseconds. A leading sign does not count. The unit selector always shows the interpretation, and you can override it.
For equivalent examples, unit-error symptoms, and the limits of digit-count inference, read the guide to Unix timestamps in seconds, milliseconds, and microseconds.
Conversion method and worked examples
Unix time counts seconds from 1970-01-01 00:00:00 UTC. The converter normalizes each input to milliseconds because the browser's Date object uses milliseconds. Seconds are multiplied by 1,000. Microseconds are divided by 1,000. Any fraction smaller than one millisecond is truncated. Negative values represent instants before the epoch.
Example: 1,700,000,000 seconds becomes 1,700,000,000,000 milliseconds, which is 2023-11-14 22:13:20 UTC. The same instant is shown in your device's local time below the UTC result. As another boundary example, auto mode reads 99999999999 as seconds and 100000000000 as milliseconds.
The UTC date field accepts a real calendar date with hours, minutes, and optional seconds. It rejects impossible dates such as February 31. The browser limits the supported range, so values outside the Date range return an error.
Sources: The Open Group explanation of seconds since the Epoch; ECMAScript Date objects.
When to use it
This converter is useful for developers, logs, APIs, databases, debugging, analytics exports, event records, and any system that stores dates as epoch values instead of readable calendar text.
Use the live epoch Unix time clock when you need the current timestamp, the milliseconds converter for unit math, or the UTC clock when you just need current Coordinated Universal Time.
UTC and local time notes
Unix timestamps represent an instant in time. The UTC display shows that instant against the shared UTC reference, while the local display uses your browser and device timezone settings. For planning across locations, use the time zone converter.
This page uses browser Date behavior. It does not sync to an external time authority, and unusual historical timezone rules can depend on the timezone data available to your device.
Accuracy and limitations
A timestamp identifies an instant. It does not contain a timezone. UTC and local output are two displays of that same instant. Choose a unit directly when the source system documents one because digit detection can be ambiguous for old, future, or unusually scaled values.
Results depend on the value entered. The current-time example is seeded from the device's system clock, and the converter checks whether a value can be converted by the browser, not whether an arbitrary timestamp has real-world meaning for a particular event.
Maintained by Suhas Sunder. See how iLoveTimers is made.
Last reviewed .
Unix timestamp converter FAQ
Is a Unix timestamp in seconds or milliseconds?
Both are common. Unix timestamps are often seconds, while JavaScript Date values are milliseconds. The converter shows both so you can copy the value your system expects.
Why does the local time differ from UTC?
UTC is the shared reference time. Local time applies your current timezone offset and daylight saving rules to the same timestamp.
Can I use this for time math?
Use this page to convert timestamps. For adding or subtracting durations, the time calculator is usually a better fit.