Unix Timestamp Converter
Convert Unix timestamps to local, UTC, ISO, and relative dates, or convert dates back to timestamps.
What is a Unix timestamp?
A Unix timestamp is the number of seconds since January 1, 1970 at 00:00:00 UTC. It is widely used in APIs, databases, logs, schedulers, and programming languages because it is compact and timezone-independent.
This converter accepts seconds or milliseconds and displays local time, UTC time, ISO format, and relative time. You can also enter a date and convert it back to a timestamp.
Practical timestamp examples
Seconds: a 10-digit value such as 1715500800 is usually a Unix timestamp in seconds.
Milliseconds: a 13-digit value such as 1715500800000 is commonly produced by JavaScript and many frontend logs.
API debugging: convert iat, exp, database fields, and scheduler timestamps to local and UTC dates before comparing them.
FAQ
Is my timestamp in seconds or milliseconds?
Most Unix timestamps are 10 digits in seconds. JavaScript Date values are usually 13 digits in milliseconds.
Why does local time differ from UTC?
UTC is timezone-neutral. Local time is adjusted by your browser timezone and daylight-saving rules.
What is ISO 8601?
ISO 8601 is a standardized date-time format such as 2026-05-16T12:30:00.000Z. It is common in APIs and logs.
Can I convert a date back to a timestamp?
Yes. Choose a local date and time, then convert it to a Unix timestamp for APIs, cron debugging, or database queries.