How to Stop the Screen Turning Off During a Presentation

To stop the screen turning off during a presentation, present from a real slide show mode that holds the display on, and for anything else turn on a keep-awake method for the length of the talk. In our test on 3 October 2026, Google Slides in Chrome held the display on only after we pressed Slideshow, and a PDF in Preview's slideshow held nothing, so the Mac would have dimmed on its normal timer. On Windows use presentationsettings /start or PowerToys Awake; on a Mac use caffeinate -d, then switch it off after.

Why the screen turns off mid-talk

Windows and macOS turn the display off after a set time with no keyboard or mouse input. On the MacBook we tested, the defaults read 2 minutes on battery and 10 minutes on the charger (pmset -g custom: displaysleep 2 and displaysleep 10). If you talk for 3 minutes on battery without touching the laptop, the screen goes dark, unless an app tells the system to keep the display on.

An app does that by holding a display-sleep assertion. On a Mac you can see who holds one with pmset -g assertions, so we used that to check which ways of presenting keep the screen on by themselves.

What we measured: which apps keep the display on

Test setup: MacBook on macOS 26.5.2, Google Chrome 154.0.8037.95, Preview, a 3-page test PDF, and a public Google Slides deck. For each case we started the presentation, waited 8 seconds, then read pmset -g assertions and looked for a line from that app.

This is the line Chrome added while the Google Slides slideshow played:

pid 4891(Google Chrome): [0x0004d6f6000593d1] 00:00:07 NoDisplaySleepAssertion named: "Blink Wake Lock"

So a browser deck is safe only while it is in slide show mode. If you present from the edit view, from a PDF viewer, or from a window you share in a call while you scroll a document, nothing holds the screen on. We had no PowerPoint or Keynote on the test Mac. Both are built to keep the display on during a full-screen slide show, but PowerPoint's edit and reading views are not slide shows, and that is where most "screen went black mid-talk" cases start.

Two more things turn the screen off that are not display sleep. A screen saver runs on its own timer, and many company laptops lock after an idle time set by IT. No app on this page overrides an IT lock policy.

Mac: keep the display on during a presentation

The quickest fix is one Terminal command before you start:

# keep the display on for 90 minutes (5400 seconds), then stop by itself
caffeinate -d -t 5400

Press Ctrl+C to stop it early. -d blocks display sleep; add -i to block system sleep too. The other flags are in caffeinate on Mac.

Without Terminal, change the timers in System Settings. On macOS Tahoe the display timers are in System Settings > Lock Screen:

Set Turn display off on power adapter when inactive to a longer time and plug in the charger; the battery timer is the short one. The screen saver timer is no longer on that page. On macOS 26.5.2 it is in System Settings > Wallpaper > Screen Saver..., in the Start Screen Saver menu:

Apps that do the same with one click, such as Amphetamine and KeepingYouAwake, are compared in the best app to keep a Mac awake. If the Mac locks rather than dims, see how to keep a Mac screen from locking.

Windows: turn on presentation settings

Windows laptops have a built-in presentation mode that keeps the computer awake and turns the screen saver off until you stop it. Run it from the Start menu or a Command Prompt:

:: start presentation mode: no sleep, no screen saver
presentationsettings /start

:: after the talk
presentationsettings /stop

Running presentationsettings with no switch opens its window, where you can also mute the speakers and set a background. It is part of Windows Mobility Center and appears on laptops, not on most desktop PCs.

If your PC does not have it, Microsoft's free PowerToys includes Awake. Pick Keep awake for a time interval, set it to the length of the talk plus 15 minutes, and turn on Keep screen on. When the timer ends, Windows goes back to its normal power plan, so you cannot forget to undo it. What Awake changes is in PowerToys Awake and Slack.

To change the timeout itself for the day, open Settings > System > Power & battery > Screen, sleep & hibernate timeouts, or run:

:: keep the screen on while plugged in, then restore 10 minutes after the talk
powercfg /change monitor-timeout-ac 0
powercfg /change monitor-timeout-ac 10

Changing only the plugged-in value does nothing on battery, so plug in the charger. The full walk-through, including the screen saver and lock settings, is in how to change the screen timeout on Windows 11.

Browser decks: Google Slides, Canva, web PDFs

Our test shows Google Slides asks Chrome for a screen wake lock in slide show mode. If you present a page that does not, such as a PDF opened in a browser tab or a web deck in its normal view, you can ask for the same lock yourself from the browser console on that tab (View > Developer > JavaScript Console, or F12):

// keep the screen on while this tab stays visible
const lock = await navigator.wakeLock.request("screen");
// after the talk
await lock.release();

In Chrome 154 this added the same "Blink Wake Lock" line to pmset -g assertions, and lock.release() removed it. The lock drops when you switch tabs or minimize the window, so run it again if you leave the tab. Extensions that do this without the console are covered in keep-awake Chrome extensions.

Checklist before you present

• Plug in the charger.
• Start the deck in slide show mode: F5 in PowerPoint, Play in Keynote, Slideshow in Google Slides.
• If you present anything else, turn on one keep-awake method: caffeinate -d, presentationsettings /start, or PowerToys Awake with Keep screen on.
• Turn the keep-awake method off after the talk.

FAQ

Why does my screen go to sleep during a PowerPoint presentation? You are probably presenting from the edit or reading view, which is not a slide show. Start Slide Show with F5, or turn on a keep-awake method for the talk.

Does Google Slides keep the screen on while presenting? In Chrome, yes, but only in slide show mode. In our test Chrome held a "Blink Wake Lock" after we pressed Slideshow, and dropped it when we pressed Esc.

Can I keep the screen on if IT locks my laptop? No app overrides a company lock policy. Ask IT for a presentation exception.