45 Minute Timer
A full class period, counted down on the big screen.
- 100% free
- No signup
- Private: stays in your browser
- Updated November 2026
About this 45 minute timer
This 45 minute timer counts down a typical class period. It's useful for tests and practice exams, long lab or project sessions, and any time you want the whole class to see exactly how much of the period is left.
Because the timer runs from the real clock, it stays exact for the full 45 minutes, even with the tab in the background. The ring turns red in the final few minutes as a quiet warning.
Need something different? The full tool lets you set anything you like: classroom timer.
What fits in forty-five minutes
Practice exam
Recreate real test timing so students learn to pace themselves.
Long lab
Plan, run and write up an experiment in one period.
Workshop session
A full writing or math workshop with mini-lesson, work time and share.
Substitute plan
Leave the timer up so the class and the sub can track the period.
Frequently asked questions
Is the 45 minute timer accurate for exams?
Yes. It counts from the system clock, so it doesn't drift, even over the full period.
Can I hide the controls during a test?
Press F for present mode. Only the time, ring and a small exit button are shown.
Will it play a sound at the end?
Yes, unless you mute it. Choose from bell, chime or beep.