Unix time (also known as Epoch time or POSIX time) is a system for describing a point in time defined as the total number of seconds that have elapsed since the Unix Epoch. Because it is represented as a single integer, it is the primary standard for timekeeping in computing, operating systems, and file formats.
The "zero point" for Unix time is 00:00:00 UTC on January 1, 1970.
It is independent of timezones and Daylight Savings Time (DST).
Computers can sort and compare integers much faster than date strings.
The native time format for Linux, macOS, and high-performance databases.
| Period | Total Seconds | Mathematical Calculation |
|---|---|---|
| 1 Hour | 3,600 | 60 × 60 |
| 1 Day | 86,400 | 24 × 3,600 |
| 1 Week | 604,800 | 7 × 86,400 |
| 1 Year (365 days) | 31,536,000 | 365 × 86,400 |