A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970, at 00:00:00 UTC. It is the standard way computers represent time internally and is used extensively in databases, APIs, log files, and programming languages.
Standard Unix timestamps are in seconds (10 digits). Some systems like JavaScript use milliseconds (13 digits). This tool auto-detects the format based on the number of digits and converts accordingly.
Frequently Asked Questions
What is the Unix epoch?
The Unix epoch is January 1, 1970, at 00:00:00 UTC. All Unix timestamps are measured as the number of seconds (or milliseconds) elapsed since this reference point.
Does this tool handle millisecond timestamps?
Yes. The tool automatically detects whether your input is in seconds (10 digits) or milliseconds (13 digits) and converts accordingly.
What is the Year 2038 problem?
Many older systems store Unix timestamps as 32-bit signed integers, which will overflow on January 19, 2038. Modern systems use 64-bit integers to avoid this issue.
Are the conversions done in my local timezone?
The tool shows results in UTC, ISO 8601, and your local timezone. When converting a date to a timestamp, the date picker uses your local timezone.
Is my data stored anywhere?
No. All conversions happen entirely in your browser using JavaScript. No data is sent to any server.