1:30 PM in 12-hour AM/PM format = 13:30 in 24-hour military time. Conversion rule: 12 AM = 00, 1-11 AM stays the same, 12 PM = 12, 1-11 PM adds 12.
12-hour to 24-hour conversion table
| 12-hour | 24-hour | 12-hour | 24-hour |
|---|---|---|---|
| 12:00 AM (midnight) | 00:00 | 12:00 PM (noon) | 12:00 |
| 1:00 AM | 01:00 | 1:00 PM | 13:00 |
| 2:00 AM | 02:00 | 2:00 PM | 14:00 |
| 3:00 AM | 03:00 | 3:00 PM | 15:00 |
| 4:00 AM | 04:00 | 4:00 PM | 16:00 |
| 5:00 AM | 05:00 | 5:00 PM | 17:00 |
| 6:00 AM | 06:00 | 6:00 PM | 18:00 |
| 7:00 AM | 07:00 | 7:00 PM | 19:00 |
| 8:00 AM | 08:00 | 8:00 PM | 20:00 |
| 9:00 AM | 09:00 | 9:00 PM | 21:00 |
| 10:00 AM | 10:00 | 10:00 PM | 22:00 |
| 11:00 AM | 11:00 | 11:00 PM | 23:00 |
💡 Did you know? The 24-hour clock was popularized by the British Royal Navy in the 18th century and the railways in the 19th century. France tried to introduce 24-hour time as part of the metric system during the French Revolution but abandoned it. Today, ISO 8601 mandates 24-hour format for international documents.
Frequently Asked Questions
1:30 PM 12-hour = 13:30 24-hour (military time). Formula: 12-hour hour 12 with AM = 00, with PM = 12. Hours 1-11 with AM stay the same. Hours 1-11 with PM add 12.
1:30 PM 12-hour = 13:30 24-hour. PM hours 1-11 add 12. So 1:00 PM = 13:00, 2:00 PM = 14:00, ..., 11:00 PM = 23:00. The hour 12 PM is the only exception — it stays 12.
12:00 AM (midnight) 12-hour = 00:00 24-hour. The hour 12 with AM is the only one that converts to 00 in 24-hour time.
12:00 PM (noon) 12-hour = 12:00 24-hour. The hour 12 with PM stays 12 (it doesn't become 24).
The 24-hour clock (also called military time) runs 00:00 (midnight) to 23:59. Hours are zero-padded (00, 01, ... 23). It's used in aviation, military, healthcare, computing, and most countries outside the US. ISO 8601 requires this format.
In Excel: =TEXT(A1, "HH:MM") formats time as 24-hour. If A1 is a real time value with PM, the format automatically shows 13:00, 14:00, etc. To convert manually: =MOD(HOUR(A1) + IF(HOUR(A1)=12,0,12)*(A1>=0.5), 24).
7:00 PM 12-hour = 19:00 24-hour. To convert any PM time: add 12 to the hour (unless it's 12 PM, which stays 12).
Most countries use 24-hour time for everything: UK, France, Germany, all of Europe, China, Japan, India, Brazil, and most of Africa and South America. Countries using primarily 12-hour with AM/PM: US, Canada, Australia, Philippines, and parts of Central America.