What can you do in 12 hours?
- Long dough fermentation
- A long shift
- Twice-daily medicine interval
12 Hours in other units
| Seconds | 43,200 |
|---|---|
| Minutes | 720 |
| Hours | 12 |
| Milliseconds | 43,200,000 |
When will it end?
The timer shows its end time as soon as you press start. Some examples of when 12 hours runs out:
| Start | Ends at |
|---|---|
| 09:00 | 21:00 |
| 12:30 | 00:30 (next day) |
| 18:00 | 06:00 (next day) |
| 22:45 | 10:45 (next day) |
What happens in that time?
| Walking (3 mph) | 36 mi |
|---|---|
| Running (6 mph) | 72 mi |
| Heartbeats (70 per minute) | about 50,400 |
| Distance light travels | 8,047.4 million mi |
| Share of a day | 50% |
Based on typical averages; individual values vary.
For any other length, use the main online timer, or convert time units with the time converter.
Frequently Asked Questions
How many seconds are in 12 hours?
12 hours = 43,200 seconds = 720 minutes = 12 hours.
Does the 12 hour timer keep running in the background?
Yes. It follows the real clock, so it ends on time even if you switch tabs. Just keep the tab open; on phones use "Keep screen awake".
Can I use my own music as the alarm sound?
Yes. Choose "Your own sound" in the sound menu and pick an audio file from your device. It's stored only in this browser and never uploaded.