Timestamp Converter
Convert a Unix timestamp to a readable date, or pick a date to get its timestamp.
Formula used
Seconds -> date:
date = new Date(seconds * 1000) // or ms * 1 if unit is milliseconds
Date -> timestamp:
epochMs = Date.parse(dateTimeLocal)
seconds = floor(epochMs / 1000)
milliseconds = epochMs
The human-readable result is shown in UTC (toUTCString).
Related calculators
Worked example
Unix timestamp: 1700000000 (seconds)
Human-readable date (UTC): Sat, 14 Nov 2023 22:13:20 GMT
The same tool also converts a picked date and time back into seconds and milliseconds.
Frequently asked questions
What is a Unix timestamp?
It is the number of seconds since 00:00:00 UTC on 1 January 1970, also called the Unix epoch. It is a timezone-independent way to store a moment in time.
Seconds or milliseconds?
This tool detects both. Values above about 10 trillion are treated as milliseconds; smaller values are treated as seconds. You can also pick the unit explicitly.
Why does my local time differ from UTC?
Unix time is always UTC. Your local clock adds your timezone offset, which is why the same timestamp shows different wall-clock times in different regions.
Does it handle dates before 1970?
Yes. Negative timestamps represent moments before the epoch, down to the limits of JavaScript's date range.