Keep your screen awake online—free, with no download

Sleep Blocker is a free online tool that keeps your screen awake using your browser's built-in Screen Wake Lock API. It can prevent the display on a compatible Windows PC, Mac, Chromebook, iPhone, iPad, or Android device from dimming, locking, or turning off while this page remains visible.

Use it while reading a long article, following a recipe, giving a presentation, watching a dashboard, or displaying information without repeatedly touching the mouse or screen. Nothing needs to be installed, and your normal screen timeout settings return as soon as the session ends.

How to prevent your screen from sleeping

Open Sleep Blocker in a compatible browser. A No limit wake session starts automatically.
Keep this page visible while you want the screen to stay on, then select End session to stop.
For a timed session, end the unlimited session, choose a duration, and select Start wake session.

When a timed session reaches zero, Sleep Blocker releases the screen wake lock automatically. Your device can then follow its normal display and sleep settings.

When a no-sleep page is useful

A browser-based no-sleep page is helpful when you need the display to remain readable for a temporary task but do not want to change a permanent device setting. Sleep Blocker is designed for visible, on-screen work rather than background automation.

Reading, studying, and following instructions

Keep a long article, digital textbook, sheet music page, tutorial, or set of repair instructions on screen without tapping the display every few minutes. A timed session is useful when you know roughly how long the reading or study period will last.

Cooking from a recipe

Keep a recipe visible while your hands are busy or messy. Place the phone or tablet where you can see it, start a wake session, and end the session when the meal is finished so the normal screen timeout can resume.

Presentations, demonstrations, and training

Prevent the browser display from dimming during an in-browser presentation, product demonstration, classroom activity, or training session. If the presentation runs in another application, keep Sleep Blocker visible in its own window or on a second screen.

Dashboards and monitoring screens

Leave a status dashboard, analytics report, build monitor, queue, clock, or other frequently checked information visible. For longer sessions, connect the device to power and use No limit, then stop the session when continuous display is no longer needed.

Video calls and listening sessions

During a long call, webinar, or lecture, you may spend more time listening than touching the keyboard. A wake lock can keep a visible browser display from timing out, but it does not simulate activity or control your availability status in the calling service.

What happens if you switch tabs?

Browsers can release a screen wake lock when its page becomes hidden or the window is minimized. Sleep Blocker requests the lock again when you return, and the countdown remains accurate in the meantime. For the most reliable result, leave this page open in a visible browser window.

Screen Wake Lock browser support

The Screen Wake Lock API is available in current versions of major browsers, but support can still vary by device, browser settings, battery level, and power-saving mode. Sleep Blocker only shows an active session after the browser grants the wake lock.

Windows, Mac, Linux, and Chromebook

Open Sleep Blocker in a current compatible browser and keep its window visible. The unlimited wake session starts automatically, or you can stop it and choose a timer. The wake session affects the display request made by that browser page; it does not permanently rewrite Windows, macOS, Linux, or ChromeOS power settings.

iPhone, iPad, and Android

Mobile browsers can support screen wake locks, but the page generally needs to remain in the foreground. Locking the phone manually, switching apps, using low-power mode, or allowing the browser to become hidden can release the lock. Mobile screens also use significant battery power, so a timer and lower brightness are sensible for longer sessions.

Read the step-by-step guide for your device:

Screen Wake Lock vs. changing the screen timeout

There are several ways to keep a screen on, and each fits a different situation:

| Method | Best for | Main consideration | | --- | --- | --- | | Sleep Blocker | Temporary, no-install sessions | The page must remain visible | | Device screen-timeout setting | Keeping the display on across apps | Remember to restore the setting later | | Installed keep-awake utility | System-wide or background tasks | Requires a download and may require permission |

Sleep Blocker is the simplest option when you need a temporary screen wake lock in a browser. For an overnight download, closed-lid computer, or background process, use an operating-system feature or dedicated utility that is designed to prevent full system sleep.

Troubleshooting a screen that still turns off

If the wake session cannot start or stops unexpectedly:

Confirm that this page is still open and visible, not minimized or hidden behind another browser tab.
Use a current browser and make sure the page is loaded securely over HTTPS.
Check whether battery saver, low-power mode, or a device policy is refusing the wake lock.
Return to the page and start the session again if the browser released it.
Remember that closing a laptop lid, pressing the device's lock button, or manually turning off the display can override a browser wake lock.

Frequently asked questions

How can I keep my screen awake without changing power settings?

Open this page and Sleep Blocker automatically starts an unlimited wake session. You can also end it, choose a timer, and start a timed session. Sleep Blocker asks your browser to keep the display on temporarily, so you do not need to change the device's permanent screen timeout settings.

Can a website prevent my computer from sleeping?

This page can prevent a compatible device's screen from dimming or locking while the page is visible. It does not promise to keep the entire computer running, preserve downloads in the background, or override every operating-system power setting.

Does it work on Windows, Mac, iPhone, and Android?

It works on those platforms when they are using a browser that supports the Screen Wake Lock API. The page must be served over HTTPS and remain visible. A browser or device may refuse the lock in low-power mode or under other system restrictions.

Does keeping the screen awake use more battery?

Yes. A display that stays lit uses more power, especially at high brightness. Use a timed session when possible, reduce the brightness to a comfortable level, and connect the device to power for long monitoring or presentation sessions.

Is it safe to use a screen wake lock?

A screen wake lock is a standard browser feature and can be released at any time by ending the session or closing the page. Be mindful that an awake, unlocked screen may leave visible information accessible to people nearby. Avoid leaving sensitive content unattended.

Will it work with the laptop lid closed?

No. Closing a laptop lid can trigger system sleep independently of the display timeout. Sleep Blocker cannot override lid switches, manual locks, shutdowns, or every device-level power policy.

Why did the wake lock stop?

The browser may release a wake lock when the page becomes hidden, the window is minimized, the battery is low, or power-saving mode is enabled. Return to the visible page and Sleep Blocker will attempt to request the lock again.

Will it keep Teams, Slack, or Zoom active?

No. Sleep Blocker keeps the display awake; it does not move the mouse, simulate keyboard input, or change presence indicators in other services.

Private by design

The wake timer runs locally in your browser. There is no account or upload. Your theme and color preferences are saved on this device so the interface looks the same when you return.

Keep your screen awake.