Turn an old laptop into a second screen

That old Windows laptop or Chromebook still has a perfectly good screen. With SpareScreen, it becomes a wireless second monitor for your Mac: open a link in its browser and it shows an extra Mac screen.

How to set it up

1. Install SpareScreen on your Mac with the line above. It opens in the menu bar.
2. Allow Screen Recording when macOS asks. That lets SpareScreen show the extra screen on your laptop.
3. Open the link in the laptop's browser. Click SpareScreen in the menu bar to see the link and its QR code, then open it on the laptop. Both need to be on the same Wi-Fi.
4. Click Allow on the Mac. An extra screen appears, shaped exactly like your laptop. Drag windows onto it like any monitor.

On the laptop, press F11 (or the full-screen key on a Chromebook) so the browser fills the screen.

What works

• Windows laptops with Chrome, Edge or Firefox.
• Chromebooks, including school and older models that still get Chrome updates.
• Linux laptops with any modern browser.
• Another Mac works too, through Safari or Chrome.

Good to know

• Keep the laptop plugged in and set it not to sleep while the lid is open, so the screen stays on.
• Use the laptop's keyboard for nothing: it's only a screen. You type and click on the Mac.
• Touch control is optional. Turn it on in the SpareScreen menu (it asks for Accessibility permission) to tap, drag, right-click and scroll on the device. Typing still happens on the Mac.
• Everyday work feels instant. Video and fast scrolling are heavier and can stutter on slow Wi-Fi; 5 GHz Wi-Fi helps.
• Streaming services stay black. Netflix, Prime Video and Disney+ block screen capture in every app like this.
• Use Wi-Fi you trust. The picture travels over your local network, never through the internet.

Questions

Can I use a Windows laptop as a second monitor for a Mac?

Yes. SpareScreen runs on the Mac; the Windows laptop only opens a link in its browser on the same Wi-Fi.

Can a Chromebook be a second screen for a Mac?

Yes. Open the link in Chrome on the Chromebook and switch it to full screen.

What does SpareScreen cost?

It's free for 7 days, then $7.99 once. It's a one-time purchase with no subscription, and one key works on up to 3 Macs.

Which Macs does it work on?

Any Mac running macOS 13 Ventura or later, with Apple Silicon or Intel.

More guides

• Use your iPad as a second monitor for Mac
• Use an Android tablet as a second monitor for your Mac (wireless
• Use your phone as a second screen for your Mac
• Sidecar alternative for iPads Sidecar doesn't support
• Sidecar not working or iPad not supported? Use any device as a Mac second screen
• Duet Display alternative with no subscription
• Luna Display alternative
• spacedesk for Mac? Here's what works on macOS instead
• Wireless second monitor for your MacBook
• Use a Chromebook as a second monitor for your Mac (wireless
• Use an Amazon Fire tablet as a second monitor for your Mac
• Use a Samsung Galaxy Tab as a second monitor for your Mac
• Use a Windows laptop as a second monitor for your Mac
• Add a second monitor to your Mac mini using a tablet or laptop you own
• Use an old iPad as a second monitor for your Mac (iPad Air 2
• Best ways to add a second screen to your Mac

Last updated October 2026.