Harmless Screen Pranks: Fake Cracks, Crashes and Boot Loops

The best screen prank borrows a few seconds of panic and hands them straight back. Everything here runs in an ordinary browser tab: nothing is installed, nothing on the device changes, and the effect disappears with a tap or the Esc key. What makes it convincing is the setup, and what keeps it funny is knowing when to stop.

The fake cracked screen

The Fake Broken Screen shows a shattered screen with a flickering, damaged display underneath. It's the classic: hand someone their phone, or slide a laptop back across the desk, and watch them find the crack.

• Pick Cracked with the arrows under the Start button before you begin, so the other person never sees a menu.
• Turn the brightness up. Cracks look more convincing on a bright screen.
• Set the scene. "I think I knocked it off the table" does more work than any effect.
• A tap anywhere ends it, so the other person usually reveals the prank themselves — which is half the fun.

The crash screens

The same tool includes the screens nobody wants to see: a Windows blue screen, the classic Windows XP stop error, a Mac restart message, a Linux kernel panic, an iPhone recovery screen and an Android "System UI isn't responding" dialog.

Match the screen to the device. A Windows blue screen on a MacBook gives the game away instantly; a Mac restart message on the same MacBook doesn't. TV static and the no-signal screen work best on a TV, or on a monitor plugged into a laptop.

The endless startup

The Boot Screen Simulator shows a Windows 10, Windows XP or macOS startup screen that never finishes loading. Leave it on a colleague's monitor while they fetch a coffee. "It's been doing that for ten minutes" is the line that sells it.

The not-quite-a-prank screensaver

The Screensaver is less of a scare and more of a slow burn. Put Matrix rain on someone's monitor and let them wonder whether they've been hacked — or start the bouncing DVD logo and take bets on whether it'll hit the corner.

Making it convincing

• Go full-screen. Always use the Start button so the browser's tabs and address bar disappear. On some phones the browser can't hide everything, so check how it looks before you hand the phone over.
• Keep your hands off the mouse. Moving it brings up the controls along the bottom of the screen, which is a giveaway.
• Time it. The moment someone sits back down or picks their phone up is when they're least suspicious.
• Keep it short. A prank that lasts ten seconds is a story. One that lasts ten minutes is an argument.

Keep it harmless

A few simple rules keep it on the right side of funny:

• Reveal it quickly. Never let someone get as far as booking a repair, restarting in a panic, or resetting their device.
• Flashing effects aren't for everyone. Several effects flicker or flash. Don't use them on anyone with photosensitive epilepsy or light-triggered migraines, or on anyone you don't know well enough to ask.
• Pick your moment. Not before a deadline, not in the middle of a presentation, and not on someone who's already having a bad day.
• Be careful with work devices. A fake crash on a shared or company computer can send people to the IT department or to a real repair shop. Make sure the reveal happens before anyone acts on it.
• Don't leave it running on an OLED screen for hours. Like any static image, a prank left on an OLED screen for a long time adds a little uneven wear. A few minutes is nothing.

How to end it

Tap anywhere or press Esc to end the cracked screen, the crash screens and the boot screens. On the screensaver, press Esc or use the Exit button in the controls.

And if you're the one who got pranked and you're reading this to check: tap the screen. If the crack disappears, your screen is fine. If it doesn't, Cracked Screen: Just the Glass, or the Display Too? will help you work out what's broken.