Unix Timestamp Converter
A Unix timestamp counts seconds since 1 January 1970 UTC and carries no timezone of its own. The local time shown uses your device's timezone; the ISO value is always UTC. A date typed without a timezone is read as local time, so add a trailing Z to force UTC.
Convert Unix timestamps into readable dates and back again, in seconds or milliseconds, with a live clock showing the current epoch time. Useful whenever a log file or database column gives you a bare number.
How it works
A Unix timestamp counts seconds from the epoch — midnight UTC on 1 January 1970. Converting to a date means multiplying to milliseconds and handing the result to the browser's date handling, which knows about leap years, leap seconds and every timezone rule.
The crucial thing to understand is that the timestamp carries no timezone. It identifies a moment, not a local time. The same number is 9am in London and 4am in New York, which is why every result here shows both the UTC form and your own local rendering of the same instant.
Going the other way, a date string without an explicit timezone is interpreted as local time. Adding Z forces UTC, and the difference between the two can be several hours.
Worked example
The timestamp 1700000000 is 14 November 2023 at 22:13:20 UTC. In milliseconds the same instant is 1700000000000 — three digits longer, which is the quickest way to tell the two apart at a glance.
The epoch itself, 0, converts to 1 January 1970 at midnight UTC. Seeing that date in an application almost always means a missing or zero value rather than a genuine record from 1970.
Common questions
What is a Unix timestamp?
The number of seconds elapsed since midnight UTC on 1 January 1970, known as the epoch. It is a single integer with no timezone attached, which is exactly why systems use it — there is no ambiguity about what moment it refers to.
Seconds or milliseconds — how do I tell?
By length. A current timestamp in seconds is ten digits; in milliseconds it is thirteen. If a date comes out in 1970, you have almost certainly passed milliseconds to something expecting seconds.
Why does the local time differ from the UTC one?
Because the timestamp itself has no timezone. The UTC line is the canonical moment; the local line is that same moment expressed in your device's timezone, including any daylight saving offset in force on that date.
How should I type a date to convert it?
ISO 8601 is the safest — 2026-08-05T09:30:00Z. Without a trailing Z it is read as your local time rather than UTC, which shifts the result by your offset. That single character is a common source of confusion.
What is the year 2038 problem?
Systems storing timestamps as signed 32-bit integers run out of room in January 2038 and wrap around to negative numbers. Modern systems use 64-bit values and are unaffected, but the issue persists in older embedded software.
Can timestamps be negative?
Yes — anything before 1970 is negative. Historical dates convert perfectly well, so a timestamp of -86400 is 31 December 1969.