Using a second screen can make work, gaming, and multitasking easier. But what if you don’t have an extra monitor? Good news—you can use your laptop as a second screen! This guide explains how to use a laptop as a monitor using simple steps, with options for both Windows and Mac users. Whether you’re extending your display or mirroring it, this setup can help you be more productive.
Why Use Your Laptop as a Monitor?
Using a laptop as a second screen can be helpful in many situations:
- Boosts Productivity: You can work on one screen while referencing another.
- Saves Space: No need to buy or make room for another monitor.
- More Screen Real Estate: Great for coding, editing, or writing tasks.
- Easy for Travel: Useful when working remotely or on the go.
Important: What You’ll Need
Before you start, make sure you have:
- Two computers: A desktop or another laptop (source computer) and your laptop (second monitor).
- A stable internet connection (for wireless options).
- Windows 10 or 11 for Miracast features (on both devices).
- For Mac users, access to Sidecar or a third-party app like Luna Display.
How to Use a Windows Laptop as a Monitor (Using Miracast)
1. Set Up the Receiving Laptop
On the laptop you want to use as a second monitor:
- Go to Settings → System → Projecting to this PC.
- Under Some Windows and Android devices can project to this PC when you say it’s OK, choose:
- Available everywhere on secure networks.
- Choose whether to require PIN or approval every time.
- Leave this window open.
2. Set Up the Main PC (Source)
On your main computer (the one you’re extending from):
- Press Windows + P on the keyboard.
- Select Extend from the menu that appears.
- Click Connect to a wireless display at the bottom.
- Choose your laptop from the list of available devices.
Once connected, your laptop screen will extend your desktop.
How to Use a Laptop as a Monitor with HDMI (Spoiler: You Can’t)
A common question is: Can I connect two laptops with an HDMI cable to use one as a monitor?
Unfortunately, no. Laptop HDMI ports are output-only, not input. This means you can’t directly use an HDMI cable to turn a laptop into a monitor. You’ll need to use software-based methods instead.
Use Third-Party Apps to Connect Laptops
If Miracast isn’t available, try these apps:
1. SpaceDesk (Windows only)
- Free and easy to use.
- Install the server on the main computer.
- Install the viewer on the laptop.
- Both devices must be on the same Wi-Fi network.
2. Splashtop Wired XDisplay
- Works with Windows and Mac.
- Requires a USB cable or Wi-Fi connection.
- Good for fast and smooth performance.
3. Luna Display (Mac & Windows)
- A paid option that uses a small hardware dongle.
- Reliable and high-quality video display.
How to Use a Mac Laptop as a Monitor (Sidecar)
If you have a MacBook and another Apple device (like an iPad or another Mac), you can use Sidecar:
Requirements:
- macOS Catalina or later.
- Devices must be signed into the same Apple ID.
- Bluetooth, Wi-Fi, and Handoff must be turned on.
Steps:
- Click the Control Center icon in the menu bar.
- Choose Screen Mirroring.
- Select your MacBook from the list.
- Choose Extend Display to use both screens separately.
Using an iPad as a Second Monitor (Bonus Tip)
No extra laptop? You can still extend your screen using an iPad:
Tools to Use:
- Sidecar (for Mac users)
- Duet Display
- Splashtop Wired XDisplay
These apps turn your iPad into a portable second monitor, perfect for working while traveling.
When to Use a Docking Station or External Display
If you need more screens, you might consider connecting your laptop to a monitor using HDMI or DisplayPort. That leads us to another common topic: how to connect two monitors to one computer. This is useful when your workflow needs more space, like coding, video editing, or comparing documents side by side.
Pros & Cons of Using a Laptop as a Second Monitor
Using your laptop as a second monitor can be a smart, money-saving move. It helps you get more screen space without buying a separate display. This setup is especially helpful when you’re working remotely, traveling, or short on desk space. But like most tech tricks, there are a few drawbacks too. Some setups need extra apps, and not all devices work well together. Let’s look at the pros and cons so you can decide if this setup is right for you.
Pros:
- No need to buy an external display
Using your laptop as a monitor saves money. You can skip the cost of an extra screen and still get a dual-monitor setup. - Useful in travel situations
When you’re on the road or working from different places, having a second screen from another laptop is super handy. No need to carry around a big, bulky monitor. - Makes multitasking easier
It’s easier to write on one screen and research on another. Or video chat on one while reviewing files on the second. You’ll get more done with less switching. - Wireless options available
You don’t always need extra cables. Tools like Miracast and SpaceDesk let you connect devices over Wi-Fi, keeping your workspace cleaner and easier to manage.
Cons:
- May lag depending on internet speed
If you’re using a wireless connection, you might notice delays. Slow or weak Wi-Fi can make the second screen lag or freeze, especially during video or gaming. - Not as sharp or responsive as a true monitor
Laptop screens weren’t designed to be second monitors. That means the display might not be as smooth or clear, especially for tasks like graphic design or fast-paced work. - Some setups need apps or adapters
You may have to install software like SpaceDesk or buy adapters, especially if your devices don’t support features like Miracast or Sidecar. - Limited by device compatibility
Not every laptop can be used as a second screen. For example, some older Windows versions or Macs might not support screen sharing without extra tools.
Common Problems and Fixes
Laptop Not Showing as a Display
- Make sure Miracast is supported on both devices.
- Update your graphics drivers.
- Both devices must be on the same network.
Laggy or Blurry Display
- Use a wired option if possible.
- Check your Wi-Fi strength.
- Close background apps to improve performance.
Miracast Not Working
- Try using SpaceDesk or another app instead.
- Restart both devices and try again.
Tips for the Best Experience
- Use Extend mode instead of Duplicate for real multitasking.
- Adjust display settings (resolution, scale) to match both screens.
- If one screen looks fuzzy, update your graphics driver.
- Keep both devices plugged in—screen sharing can drain batteries fast.
Frequently Asked Questions
Can I use my MacBook as a second monitor for a Windows PC?
Not natively. You’ll need apps like Luna Display, Duet Display, or SpaceDesk (some compatibility issues may occur).
Can I use a laptop as a second monitor without Wi-Fi?
Yes—some apps like Splashtop Wired XDisplay use a USB connection instead of Wi-Fi.
Is using a laptop as a monitor good for gaming?
Not really. Due to lag and resolution limits, it’s better to use a real monitor for gaming.
Final Thoughts
Knowing how to use your laptop as a monitor can save you time, money, and space. Whether you’re working from home or on the go, this method gives you flexibility. There are many options—Miracast for Windows, Sidecar for Macs, or apps like SpaceDesk and Duet Display.
If you need even more screen space, you can always look into how to connect two monitors to your main computer. But for a quick dual-screen setup, using your laptop as a second monitor works well—especially when you’re in a pinch.