How to Convert a Unix Timestamp
Epoch timestamps are everywhere in logs, databases and API responses, and completely unreadable at a glance — a ten-digit number tells you nothing about whether an event happened last week or last year. Paste one here and it's converted immediately, with the unit detected automatically from the number's magnitude: ten digits is seconds, thirteen is milliseconds, sixteen is microseconds. That detection matters, because mixing up seconds and milliseconds is the single most common timestamp bug, landing you either in 1970 or fifty thousand years in the future. Every result is shown in both UTC and your own time zone, as an ISO 8601 string suitable for APIs, as the standard UTC string, and as a plain-English relative time. The reverse direction works just as flexibly: type a date in almost any reasonable format and get epoch seconds and milliseconds back. A live clock shows the current epoch time with a button to load it instantly, which saves hunting for the number when you just need "now". Every row has its own copy button, and everything runs in your browser.
Paste a timestamp
Enter epoch seconds, millis or micros — the unit is detected for you.
Read every format
UTC, local, ISO 8601 and relative time all at once.
Or go backwards
Type a date below to get epoch seconds and milliseconds.
What Is Epoch Time?
A count from 1970
Unix time counts the seconds elapsed since 1 January 1970 at 00:00:00 UTC, ignoring leap seconds. Because it's a single number in a fixed zone, it's unambiguous across systems and trivial to compare or sort.
Seconds versus milliseconds
Unix tools and JWT claims use seconds; JavaScript and Java use milliseconds. Passing one where the other is expected is the classic timestamp bug, which is why this tool detects and labels the unit for you.
Common Use Cases
Read log timestamps
Turn an epoch value in a log line into a readable date instantly.
Debug JWT expiry
Check what an exp or iat claim actually means in real time.
Database values
Interpret timestamp columns stored as integers.
API responses
Decode created_at and updated_at fields returned as epoch numbers.
Schedule a job
Work out the epoch value for a future date you need to set.
Compare events
See how long ago something happened with relative time.
Cross-time-zone work
View the same moment in UTC and your local zone together.
Spot unit mistakes
Catch a seconds-versus-milliseconds mix-up immediately.
Tips & Best Practices
Always store timestamps in UTC
Convert to a local zone only for display; storing local times invites daylight-saving bugs.
Check the digit count
Ten digits is seconds, thirteen is milliseconds. Confirming this catches most timestamp bugs.
Use ISO 8601 in APIs
An ISO string with an explicit offset is unambiguous and readable by both people and machines.
Remember JWT uses seconds
The exp, iat and nbf claims are epoch seconds, not milliseconds — a frequent source of errors.
Beware the 2038 problem
Systems storing epoch seconds in a signed 32-bit integer overflow in January 2038. Use 64-bit values.
Epoch has no time zone
A timestamp is a single moment. Any zone you see is just a rendering of it.
Troubleshooting
The date lands in 1970
A millisecond value was probably read as seconds. Check the digit count — thirteen digits means milliseconds.
The date is thousands of years away
The opposite mistake: seconds treated as milliseconds. This tool detects the unit automatically to avoid it.
My date string won't parse
Try an unambiguous format such as 2024-05-12T08:00:00Z. Formats like 05/12/2024 differ by country.
Local time looks an hour off
Daylight saving. Your local rendering shifts with DST, while the underlying UTC timestamp never changes.
Frequently Asked Questions
How do I convert a Unix timestamp for free?
Paste the number above and the date appears instantly in UTC, local, ISO and relative form — free, no signup.
What is a Unix timestamp?
The number of seconds since 1 January 1970 at 00:00:00 UTC, used as a universal way to record a moment in time.
Does it detect seconds versus milliseconds?
Yes. The unit is inferred from the number's size — ten digits is seconds, thirteen milliseconds, sixteen microseconds.
Can I convert a date back to a timestamp?
Yes. Enter a date in the second field and you get epoch seconds and milliseconds.
Which date formats are accepted?
ISO strings, plain dates like 2024-05-12, and natural forms like 12 May 2024. ISO with an offset is the most reliable.
Does it show my local time zone?
Yes. Results appear in both UTC and your browser's detected time zone.
What is relative time?
A plain-English description like three hours ago or in two days, so you can judge a timestamp at a glance.
What does timestamp 0 mean?
1 January 1970 at 00:00:00 UTC — the Unix epoch itself.
Do negative timestamps work?
Yes. Negative values represent moments before 1970.
What is the 2038 problem?
Signed 32-bit systems storing epoch seconds overflow in January 2038. Modern systems use 64-bit values instead.
Does epoch time include leap seconds?
No. Unix time deliberately ignores leap seconds, which keeps the arithmetic simple.
Why does JWT use seconds?
The JWT specification defines exp, iat and nbf as epoch seconds, unlike JavaScript's millisecond convention.
Is anything sent to a server?
No. All conversion happens in your browser, so nothing leaves your device.
Can I copy a specific format?
Yes. Every output row has its own copy button.
What's the live clock for?
It shows the current epoch time, ticking every second, with a button to load it into the converter.
Does daylight saving affect the timestamp?
No. The timestamp is fixed; only the local rendering of it shifts with DST.
Does it work on phones?
Yes, in any modern browser on Windows, Mac, Android or iPhone with nothing to install.
Is this tool really free?
Completely free, forever — no account, no ads and no premium wall.
100% free · No signup · Processed in your browser · Data never sent
Last updated: August 2026 · FlipMyFormat Unix Timestamp Converter
Written and maintained by the FlipMyFormat team · Runs entirely in your browser