How to Use a Laptop as a Second Monitor (Windows/macOS)
Need more screen space without buying a new monitor? Good news: you can use your spare laptop as a second display for your main computer. Whether you’re using Windows or macOS, there are a few different ways to set this up—both wired and wireless. In this guide, we’ll walk you through the step-by-step process of using your laptop as a second monitor.
Why Use a Laptop as a Second Monitor?
Expanding your digital workspace has many advantages:
Increased productivity: Run multiple apps side-by-side.
Better multitasking: Keep communication tools open while you work.
Cost-effective: No need to purchase another monitor.
Method 1: Using Miracast (Windows Only)
If both of your Windows devices support Miracast, you can use it to wirelessly project your main PC’s screen onto your laptop.
Steps:
On the laptop (second display), go to Settings > System > Projecting to this PC.
Choose Available everywhere or Available on secure networks.
Enable Ask to project to this PC if needed.
On your main PC, press
Windows + Kand select the laptop from the list.Approve the connection request on the laptop.
Your laptop will now act as a second screen.
Note: Performance may vary depending on your Wi-Fi network quality.
Method 2: Using AirPlay (macOS Only)
If you’re using two Mac devices, macOS Monterey and later lets you use AirPlay to Mac to share screens wirelessly.
Steps:
On the laptop (Mac), open System Settings > General > AirPlay & Handoff.
Turn on AirPlay Receiver.
On your main Mac, click the Control Center icon in the menu bar.
Select Screen Mirroring and choose your laptop.
Your laptop will now mirror or extend the screen.
Method 3: Using Third-Party Apps (Cross-Platform)
For setups involving Windows and macOS devices, or for more customization, try third-party apps.
Popular Options:
Spacedesk (Windows host, Windows/Android/iOS viewer)
Luna Display (macOS/Windows)
Duet Display (Windows/macOS/iPad)
Deskreen (Web-based solution)
General Steps:
Install the software on both the main device and the laptop.
Connect both devices to the same Wi-Fi network (or use USB for better performance).
Follow the app-specific instructions to link and extend the display.
Method 4: Using HDMI/USB-C Cables (Not Common for Laptops)
Most laptops don’t support video input—only output. So using an HDMI cable to link two laptops as display/input devices typically won’t work unless you’re using:
Capture cards (complicated and with input lag)
Specialized docking solutions (pricey and niche)
Wired options are more feasible when connecting to external monitors, not another laptop.
Troubleshooting Tips
Not detecting display? Make sure both devices are on the same Wi-Fi.
Low resolution or lag? Try a wired (USB) connection or reduce graphics load.
Can’t find the device? Double-check system permissions and app firewall access.
Final Thoughts
Turning your laptop into a second monitor is a smart way to boost productivity without spending extra money. With native tools like Miracast or AirPlay, and powerful third-party apps like Duet Display or Spacedesk, it’s easier than ever to set up a multi-display workspace.
Just choose the right method based on your devices and preferences, and enjoy the benefits of extra screen real estate!