Set alarm for 12:45 AM
Recently used Functions
| Alarm 11:59 AM | 11:59 AM |
| Alarm 11:59 PM | 11:59 PM |
| Alarm 6:00 AM | 6:00 AM |
| Alarm 7:00 AM | 7:00 AM |
| Alarm 8:00 AM | 8:00 AM |
| Alarm 9:00 AM | 9:00 AM |
| Alarm 10:00 AM | 10:00 AM |
| Alarm 12:00 PM | 12:00 PM |
| Alarm 7:55 PM | 7:55 PM |
| Alarm 6:55 PM | 6:55 PM |
Bedtimes for a 12:45 AM alarm
Waking mid-cycle is what makes an alarm feel brutal. Working back from 12:45 AM in 90-minute blocks — plus a quarter of an hour to drop off — gives these targets.
| 3:31 PM (the night before) | 6 sleep cycles | 9 hours of sleep |
| 5:01 PM (the night before) | 5 sleep cycles | 7.5 hours of sleep |
| 6:31 PM (the night before) | 4 sleep cycles | 6 hours of sleep |
These are planning figures, not medical advice — cycle length varies between people and from night to night.
What 12:45 AM looks like elsewhere
Midnight alarms are usually about deadlines rather than waking up — end-of-day cutoffs, date changes, and timed releases.
| 12-hour clock | 12:45 AM |
| 24-hour clock | 00:45 |
| Military time | 0045 |
| Relative to midday | 11h 15m before midday |
| Since midnight | 45 minutes (3% of the day) |
| Until midnight | 1395 minutes |
If you set this alarm right now it would ring in about 3h 33m, tomorrow.
About setting an alarm for 12:45 AM
What time do I need to sleep to wake up at 12:45 AM?
To get about 7.5 hours you would fall asleep around 5:01 PM, or 3:31 PM for a fuller 9 hours. Both allow roughly 15 minutes to drop off and finish on a complete sleep cycle.
What is 12:45 AM in 24-hour time?
12:45 AM is 00:45 on a 24-hour clock, written 0045 in military and aviation formats. It sits 11h 15m before midday and 45 minutes after midnight.
Will this 12:45 AM alarm work if I close the tab?
No. The alarm runs in the page, so the tab has to stay open, though it can be in the background and it keeps working without an internet connection once loaded. Bookmark the page and the 12:45 AM setting is restored when you open it again.
How the 12:45 AM alarm works
Everything is configured for 12:45 AM on this page. Choose a sound if you want one, press Set Alarm, and the countdown to 12:45 AM begins. Bookmark it to skip the setup entirely next time.
Set the hour and minute for the online alarm clock. Once you set the hour and minute for the online alarm clock, the alarm message will appear, and the preselected sound will play at the set time. You can also click the 'Test' button to preview the alert and check the sound volume.
You can customize the alarm clock's appearance, including text color, type, and size, and these settings will be saved for the next time you open your web browser.
The online alarm clock won't work if you close your browser or shut down your computer, but it can work without an internet connection. This free online alarm clock will reliably wake you up.
You can add links to online alarm clocks with different time settings to your browser's Favorites. Opening one of these links will automatically set the alarm clock to the predefined time.