Military Time Chart & Conversion Guide
In the civilian world, most people keep track of time using a 12-hour clock, dividing the day into AM (ante meridiem) and PM (post meridiem). However, in fields like aviation, shipping, medicine, military operations, and manufacturing, time must be kept with absolute precision and zero ambiguity. This is where 24-hour time—commonly referred to in North America as **military time**—becomes essential. In this guide, we provide a complete military time conversion chart and explain how to read, write, and calculate hours using the 24-hour system.
Table of Contents
1. What is Military Time?
Unlike the standard 12-hour system, which resets after 12:00 PM, the 24-hour system runs continuously from midnight to midnight. Midnight is written as **0000** (or sometimes **2400**), and every hour that passes simply increments the number.
While the military format deletes the colon (e.g. 1730 instead of 17:30) and is pronounced "seventeen-thirty hours," standard 24-hour clocks in transportation and medicine often retain the colon (e.g. 17:30).
Key Terminology Rules
- 0000 to 0900: Pronounced with a leading "zero" (e.g. 0615 is "zero-six-fifteen").
- 1200: High noon, pronounced "twelve-hundred."
- 1300 to 2400: PM hours, continuing sequentially up to midnight.
2. The 12-Hour to 24-Hour Conversion Chart
Refer to this quick-lookup table to map standard times directly to military time:
| Standard Time (12-Hour) | 24-Hour Clock | Military Time (Written) | Pronunciation |
|---|---|---|---|
| 12:00 AM (Midnight) | 00:00 | 0000 | "Zero-hundred hours" |
| 6:00 AM | 06:00 | 0600 | "Zero-six-hundred hours" |
| 12:00 PM (Noon) | 12:00 | 1200 | "Twelve-hundred hours" |
| 1:00 PM | 13:00 | 1300 | "Thirteen-hundred hours" |
| 6:00 PM | 18:00 | 1800 | "Eighteen-hundred hours" |
| 11:00 PM | 23:00 | 2300 | "Twenty-three-hundred hours" |
3. Easy Rules for Quick Conversion
You don't need to check a chart every time. Use these simple conversion rules:
- For AM Hours (1:00 AM to 11:59 AM): Keep the hour number the same, add a leading zero if it is a single digit, and remove the colon. *(e.g. 8:30 AM becomes 0830).*
- For PM Hours (1:00 PM to 11:59 PM): Simply **add 12** to the hour and remove the colon. *(e.g. 5:15 PM ➔ 5 + 12 = 17 ➔ 1715).*
- For Midnight: 12:00 AM is written as **0000**.
4. How to Calculate Hours and Subtract Time
One of the primary benefits of military time is that it simplifies subtracting times to find elapsed hours worked. Because there are no "AM" or "PM" tags to manage, you can subtract directly.
Subtracting Time Example
If an employee clocks in at **0830** (8:30 AM) and clocks out at **1715** (5:15 PM):
1715 - 0830 = ?
Since 15 minutes is less than 30 minutes, borrow 60 minutes from the hour: 1715 becomes **16:75**.
Now subtract: 16:75 - 08:30 = **08:45** (8 hours and 45 minutes worked).
5. Using a Time Card Calculator
Calculations with hours and minutes can become complex, especially when calculating weekly break penalties or decimal hour conversions. Use our free, interactive military time card calculator on the home page. It converts input clocks dynamically, subtracts break times, and returns precise weekly payroll hours automatically.