EpochFlow
Paste a timestamp in seconds, milliseconds, microseconds or nanoseconds and read it in any time zone, with the offset that actually applied at that moment and whether daylight saving was in force. The same instant is shown as a Windows FILETIME, .NET ticks, an Excel serial and a Julian day.
See how it worksSeconds (or ms, µs, ns) since 1970-01-01 UTC
The date above is wall-clock time in UTC.
How it works
1Paste the number
Seconds, milliseconds, microseconds or nanoseconds. The guess is shown, and you can overrule it.
2Pick the zone
Every IANA zone your browser knows, with its offset at that exact instant — not today's.
3Compare the systems
The same instant as a Windows FILETIME, .NET ticks, an Excel serial and a Julian day.
4Read it in your language
Weekday, full date and "two years ago" come from Intl, so they are right in all nine languages.
What it actually does
Nanoseconds survive
Timestamps are carried as BigInt, so a nanosecond value is not rounded off the way a JavaScript number rounds it.
You choose the unit
Seconds, ms, µs and ns, detected by which reading lands on a believable date and overridable at any time.
Real time zones
Any IANA zone, with the offset that applied at that instant rather than the one in force today.
Tells you about DST
Says whether the instant fell in daylight saving, and what the zone's standard offset is.
Not only Unix
Windows FILETIME, .NET ticks, Apple/Cocoa, Excel serials and Julian days, both ways.
Never leaves the page
Everything is computed in your browser. Nothing is uploaded and nothing is stored.
Frequently Asked Questions
Is my data sent to any server?+
No. Every conversion runs inside your browser using its own time-zone database. Nothing is uploaded and nothing is stored between visits.
How does it know whether my number is seconds or milliseconds?+
It tries each unit and keeps the one that lands on a believable date, then tells you which unit it chose and what year that gives. If the guess is wrong — and for microseconds in an unusual range it can be — the unit buttons overrule it.
Why does the offset change depending on the date?+
Because zones move with daylight saving and their rules have changed over the years. The offset shown is the one that applied at the instant you entered, not the one in force today, and the panel says whether that instant was in daylight saving.
What are FILETIME, .NET ticks and Excel serials?+
Other ways of counting time. FILETIME counts 100-nanosecond ticks from 1601 and shows up all over Windows; .NET ticks count the same size unit from year 1; an Excel serial counts days from 1899-12-30, keeping the spreadsheet's famous 1900 leap-year bug. All of them convert both ways here.
Will a nanosecond timestamp keep its digits?+
Yes. Timestamps are held as BigInt rather than as ordinary numbers, so 1700000000123456789 comes back exactly instead of being rounded to the nearest few hundred nanoseconds.