Wake me up in 23 hours 58 minutes. Set timer for 23 hours 58 minutes. Set the alarm for 23 hours 58 minutes from now. It is a free and easy-to-use countdown timer.
Set this 23 hours 58 minutes timer and let the countdown start. Use it to control the time limit of any activity and be notified when that limit has been reached. When the countdown stops, an alarm sound will ring.
Start 23 hours 58 minutes timer.