21-minute Timer
This 21-minute timer is designed to be easy to use and ready to go. To change the time just input your desired duration and click "set." The timer can run in fullscreen mode with a progress bar to show you how much time is remaining. It can also be used in a vertical or horizontal mirrored display, making it ideal for use with teleprompters. With just one click, this browser-based timer is ready to go.
Fun Fact
21 minutes is the average length of a power nap, according to a study published in the journal Sleep Medicine. The study found that power naps of 21 minutes or less can improve alertness, cognitive function, and performance, while longer naps can cause sleep inertia, which is the feeling of grogginess and disorientation that can occur after waking up from deep sleep.
Share the timer via link
If you want to share this timer via link with others, then try out the full version of Stagetimer. It's free and doesn't require any login to use: Create a free sharable timer.