How Military Time Works
Military time (also known as the 24-hour clock) is a method of keeping time where the day runs from midnight to midnight, divided into 24 hours. It eliminates the need for "AM" or "PM" designations, which prevents confusion in industries where precision is critical—like healthcare, aviation, the military, and payroll timesheets.
AM Hours (Morning)
For morning hours from 1:00 AM to 9:59 AM, you simply add a zero to the beginning and remove the colon.
Example: 8:00 AM becomes 0800 (pronounced "zero eight hundred").
PM Hours (Afternoon)
For afternoon and evening hours (from 1:00 PM to 11:59 PM), you simply add 12 to the hour.
Example: 3:00 PM becomes 1500 (3 + 12 = 15).
Special Cases: Noon and Midnight
The two most confusing times to convert are exactly noon and midnight:
- 12:00 PM (Noon) is simply written as 1200 in military time.
- 12:00 AM (Midnight) is written as 0000 (or occasionally 2400 depending on the exact usage, though 0000 is standard).
Why do timesheets use military time?
Using a 24-hour clock makes it significantly easier to mathematically calculate total hours worked. If an employee works from 8:00 AM to 5:00 PM, subtracting 8 from 5 yields a negative number. But if you use military time (1700 - 0800), you can easily subtract 8 from 17 to get 9 hours.