Unix Timestamp Converter
Paste an epoch timestamp to get local, UTC and ISO dates — or pick a date to get its timestamp.
- Local time
- UTC
- Unix seconds
- Unix milliseconds
- ISO 8601
How to use
- Paste a Unix timestamp — 10-digit seconds and 13-digit milliseconds are detected automatically. “Now” fills in the current time.
- Or pick a date and time in the second field to convert the other way.
- Copy any of the outputs: local time, UTC, seconds, milliseconds or ISO 8601.
Examples
Decode a log entry
A log shows 1755302400. Paste it to see it is 2025-08-16 00:00:00 UTC — and what that was in your local time zone.
Set an expiry timestamp
Pick 2026-12-31 23:59 in the date field to get the epoch seconds your API expects for an expiry value.
Reading a timestamp from a log
Log lines and API payloads often carry epoch values rather than readable dates. Converting one tells you when an event actually happened in your own time zone, which is the first step in matching a log entry against something a user reported.
Setting an expiry value
Tokens, cache entries and scheduled jobs are usually configured with an absolute epoch value. Converting the human date you want into a timestamp avoids the arithmetic errors that come from adding seconds by hand — an hour is 3,600 and a day is 86,400, and mixing those up is a common source of expiries that are off by a factor of 24.
Checking whether a value is seconds or milliseconds
A ten-digit number is seconds and a thirteen-digit number is milliseconds. Feeding milliseconds into a seconds-based function produces a date tens of thousands of years in the future, which is the giveaway. Converting the raw value is the quickest way to confirm which unit an unfamiliar API is using.
FAQ
What is a Unix timestamp?
The number of seconds elapsed since 1970-01-01 00:00:00 UTC (the Unix epoch). Many systems use milliseconds instead — the same number with three extra digits.
How does the tool know if my number is seconds or milliseconds?
Values with absolute size below 10^12 are treated as seconds, larger ones as milliseconds. Current dates are 10 digits in seconds and 13 in milliseconds, so the detection is unambiguous for realistic values, and the tool shows which unit it assumed.
Which time zone are the results in?
Three forms are shown at once: your device’s local time zone, UTC, and the ISO 8601 string (in UTC, ending with Z). The timestamp itself is time-zone independent.
Are negative timestamps valid?
Yes — they represent dates before 1970. For example −86400 is 1969-12-31 00:00:00 UTC.
Why does the same timestamp show a different date for someone else?
Because a Unix timestamp is a single moment in UTC, and the readable date depends on the viewer time zone. The same value is 2 January in Seoul and 1 January in New York. When comparing timestamps with someone in another country, agree on whether you are quoting UTC or local time before comparing.
Does the value account for leap seconds?
No, and that is by design. Unix time treats every day as exactly 86,400 seconds and simply repeats or skips a value around a leap second. This keeps arithmetic simple, at the cost of the timestamp not being a true count of elapsed seconds. For everyday use the difference never matters.
What is the 2038 problem?
Systems that store the timestamp in a signed 32-bit integer overflow on 19 January 2038 and wrap to a negative value, reading as 1901. Modern platforms use 64-bit values and are unaffected, but the limit still appears in older embedded systems and in database columns that were defined decades ago.