Unix Timestamp & Epoch Converter
A Unix timestamp counts the number of seconds that have passed since January 1, 1970, 00:00:00 UTC — commonly called "the epoch." It's the standard way computers store and compare dates internally, and this tool converts between that raw number and a human-readable date in both directions.
How to Use It
The Timestamp → Date tab takes any Unix timestamp — in seconds or milliseconds — and shows the matching local time, UTC time, and ISO 8601 format. The Date → Timestamp tab does the reverse: pick a date and time, specify whether it should be read as your local time zone or UTC, and get the equivalent timestamp in both seconds and milliseconds.
Unix time is traditionally measured in seconds, but JavaScript's Date.now() and many APIs return milliseconds instead — a 13-digit number rather than 10. If your conversion looks decades off, you're almost certainly using the wrong unit toggle.
Tips & Tricks
Check the digit count as a sanity check. A current-day timestamp in seconds is 10 digits; in milliseconds, it's 13. Any timestamp far outside that range usually means the wrong unit was used.
Use UTC for logs and APIs. Most server logs, databases, and third-party APIs store timestamps in UTC — converting them to your local time zone here can make debugging much faster.
ISO 8601 is the safest format to share. Unlike locale-formatted dates, an ISO string like 2026-09-07T12:00:00Z is unambiguous across every timezone and system.
Frequently Asked Questions
What is the Unix epoch?
It's the reference point — midnight UTC on January 1, 1970 — from which Unix time is measured. A timestamp of 0 corresponds to that exact moment.
Does Unix time account for leap seconds?
No. By convention, Unix time ignores leap seconds and treats every day as exactly 86,400 seconds, which keeps the math simple at the cost of a small, well-documented drift from true UTC over long periods.
Can this handle dates before 1970?
Yes. Timestamps before the epoch are represented as negative numbers, and this converter handles them correctly in both directions.