Good
The timer counts steadily, pause and reset respond instantly, fullscreen fills the display, and with Wake Lock active the screen stays on for the whole session.
24h Timer / Screen Awake Tool
Run a clean long-duration timer with fullscreen mode and optional Wake Lock support to reduce screen sleep interruptions during study, meetings, testing sessions and practical troubleshooting.
Wake lock not requested.
Timer
00:00:00
Displays hours, minutes, and seconds for long sessions.
About the online timer and screen-awake tool
This is a clean, fullscreen-capable browser timer with pause, reset and one extra feature that most timers lack: Wake Lock support, which asks the operating system to keep the screen awake while the timer runs. That combination makes it useful for study blocks, workshops, exams, cooking and any situation where a visible, always-on count matters.
The timer runs entirely in your browser tab — no account, no app, nothing installed. Fullscreen mode turns any laptop or spare monitor into a wall clock readable across a room, and because the display is designed for long sessions it will happily run past 24 hours.
Wake Lock deserves a caveat: it is a polite request, not a command. Battery-saver modes, managed work devices and some operating systems can still dim or sleep the screen, so for anything critical, plug the device in and check the screen-sleep setting as a backup. For irreplaceable timing — an exam you are invigilating, a live event — pair it with a second clock.
What it looks like in use
Using the timer result
The timer gives you a clear elapsed-time display with pause, reset, fullscreen and Wake Lock support where the browser allows it.
What this test checks
- Elapsed time in hours, minutes and seconds for long-running sessions.
- Pause and reset controls for meetings, study blocks, tests and troubleshooting windows.
- Fullscreen display for visibility across a room or during a focused task.
- Wake Lock availability, which may help prevent the screen sleeping on supported devices.
How to understand your results
- A good timer session keeps counting visibly while the browser tab remains active.
- Wake Lock is best effort. Battery saver, managed devices and operating-system policy can still dim or sleep the screen.
- For critical timing, use a dedicated timer or clock as a backup, especially during exams, production work or live events.
- If the browser throttles background tabs, keep the timer visible and avoid heavy background work.
Common problems and fixes
Screen still sleeps
Disable battery saver, keep the device plugged in and check display sleep settings.
Timer pauses in background
Keep the tab foregrounded for best accuracy and avoid putting the device to sleep.
Fullscreen unavailable
Some browsers block fullscreen until after a direct button press or inside restricted environments.
Wake Lock unsupported
Use browser and OS power settings as a fallback when the Wake Lock API is not available.
FAQ
Can this run beyond 24 hours?
Yes. The display is designed for long sessions and continues counting beyond one day.
Is it suitable for official timing?
Use it as a convenient browser timer, not as certified timing equipment.
Does Wake Lock drain battery?
Keeping the screen awake uses more power. Plug in for long sessions where possible.
What is Wake Lock, exactly?
It is a browser feature that asks the operating system not to sleep the screen while a page needs it — the same mechanism navigation apps use. Support varies by browser and is always subordinate to system power policy.
Will the timer keep counting if my laptop sleeps?
No timer can run while the machine itself is asleep. Keep the device awake — that is precisely what the Wake Lock option and a plugged-in power supply are for.
Can I use this to keep my screen awake without timing anything?
Yes. Start the timer, enable Wake Lock and ignore the count — many people use the page purely as a screen-awake tool during presentations or downloads.
Browser-based test disclaimer
TestMyPC results are browser-based and may vary depending on your device, browser, operating system, permissions, drivers, connection, power settings and connected accessories. Use these tools as practical first checks, then confirm important faults with operating-system diagnostics, manufacturer tools or a qualified technician where needed.