How this countdown works
The timer above checks your device's clock every second and counts down to the next 12:00. Because "12:00" can mean morning or afternoon, it shows the one that comes first and also tells you how long until the other one. Change the time in the box to count down to any other time.
12:00 in 24-hour time
- 12:00 AM = 00:00 (just after midnight)
- 12:00 PM = 12:00 (just after noon)
Working it out by hand
Subtract the current time from 12:00. If the minutes go negative, borrow 60 minutes from the hours. If the result is negative overall, add 12 hours (to reach the next 12:00) or 24 hours (to reach the same 12:00 tomorrow). For example, from 1:50 to 3:30 is 1 hour 40 minutes.
Need to add up hours across several shifts instead? Try the hours calculator, or use the time calculator to add or subtract durations.