12-hour to 24-hour converter (AM/PM)

3:00 PM = 15:00
Converts both ways, live12:00 AM = 00:00 · 12:00 PM = 12:00
Home → 12/24-hour converter

Type a time in 12-hour format (with AM or PM) and instantly see the 24-hour equivalent, or go the other way. The converter also settles the classic 12 AM vs 12 PM confusion and shows the military time notation.

12-hour (AM/PM)
24-hour

Table of all 24 hours of the day

Equivalence between 24-hour, 12-hour and military time
24-hour12-hourMilitaryPeriod
00:0012:00 AM0000midnight
01:001:00 AM0100night
02:002:00 AM0200night
03:003:00 AM0300night
04:004:00 AM0400night
05:005:00 AM0500night
06:006:00 AM0600morning
07:007:00 AM0700morning
08:008:00 AM0800morning
09:009:00 AM0900morning
10:0010:00 AM1000morning
11:0011:00 AM1100morning
12:0012:00 PM1200noon
13:001:00 PM1300afternoon
14:002:00 PM1400afternoon
15:003:00 PM1500afternoon
16:004:00 PM1600afternoon
17:005:00 PM1700afternoon
18:006:00 PM1800evening
19:007:00 PM1900evening
20:008:00 PM2000evening
21:009:00 PM2100evening
22:0010:00 PM2200evening
23:0011:00 PM2300evening

The rules in two lines

12-hour to 24-hour: AM keeps the hour (except 12 AM, which is 00). PM adds 12 (except 12 PM, which stays 12). 24-hour to 12-hour: 00 becomes 12 AM, 01-11 stay AM, 12 becomes 12 PM, and 13-23 subtract 12 and take PM. Minutes never change.

Midnight and noon: the 12 AM / 12 PM trap

AM stands for ante meridiem (before midday) and PM for post meridiem (after midday). Noon is exactly midday, so it is neither before nor after, and the labels become ambiguous. The convention used by most style guides and software is: 12:00 AM is midnight (the start of the day, 00:00) and 12:00 PM is noon (12:00). Many people mix them up, and a "12 AM meeting" can mean either midnight at the start or at the end of the date. To be safe, write "noon" or "midnight", add the date, or use 24-hour time, where there is no ambiguity. The same care applies to 12:30 AM (half an hour after midnight, 00:30) and 12:30 PM (half an hour after noon, 12:30).

Military time notation

Military time is the 24-hour clock written as four digits with no colon or AM/PM: 0800, 1315, 2359. It is spoken digit by digit or in pairs: 0800 is "zero eight hundred", 1315 is "thirteen fifteen", and 1300 is "thirteen hundred". Midnight is 0000 ("zero hundred") and the last minute of the day is 2359. Military time is also standard in aviation, hospitals, emergency services and logistics, where a mistaken AM or PM is costly. Some systems write 2400 for the end of the day; it is the same moment as 0000 of the following day.

Examples

Need to convert a time between cities rather than between formats? Use the time zone converter (it has a 12/24-hour switch), the hours calculator to add or subtract time, or the online clock to see the current time. Zones and offsets are explained in the time zones guide.

Frequently asked questions

How do I convert 12-hour time to 24-hour time?

For AM, keep the hour, except 12 AM, which becomes 00. For PM, add 12, except 12 PM, which stays 12. Examples: 3:45 PM = 15:45, 9:10 AM = 09:10, 12:30 AM = 00:30 and 12:30 PM = 12:30.

How do I convert 24-hour time to 12-hour time?

From 01:00 to 11:59 it is AM with the same hour. From 13:00 to 23:59, subtract 12 and use PM (18:20 = 6:20 PM). 00:xx becomes 12:xx AM and 12:xx becomes 12:xx PM.

Is 12 AM midnight or noon?

12 AM is midnight (00:00) and 12 PM is noon (12:00). AM means "before midday" and PM "after midday"; since noon and midnight are neither before nor after, the convention causes confusion. To avoid mistakes in contracts and tickets, write "midnight" or use 24-hour time.

What time is 00:00? And 24:00?

00:00 is midnight at the start of the day (12:00 AM). 24:00 sometimes appears to mean the end of the day, the same instant as 00:00 of the next day; in schedules and tickets, prefer 23:59 or 00:00 with the correct date.

What is military time?

It is 24-hour time written with four digits and no colon: 0800 (8 am), 1530 (3:30 pm). In the military and aviation it is spoken "zero eight hundred" or "fifteen thirty". It is the same 24-hour clock in a compact notation.

Which format does Brazil use?

Brazil uses 24-hour time in official writing (bus and flight schedules, exams, government), although people say "three in the afternoon" in speech. AM and PM are common in English, mainly in the US, Canada, Australia and India.