So, you’ve got a second device—maybe a desktop or another laptop—and you’re wondering if you can just plug it into your laptop to get a bigger or extra screen. The idea of using your laptop as a monitor sounds super handy, right? But is it actually possible? And if yes, how do you do it without pulling your hair out? Let’s break it down step by step.
Is It Possible to Use a Laptop as a Monitor for Another Device?
The quick answer: sometimes, yes—but not in the way you might think. Unlike traditional monitors, most laptops don’t have video input ports. They have output ports—meaning, they send video signals out to external devices, not the other way around.
Think of it like this: your laptop’s screen is tightly integrated with its own hardware, so it’s not designed to receive video from another computer’s graphics card via HDMI or DisplayPort. So if you’re picturing hooking up an HDMI cable from your desktop’s graphics card directly into your laptop’s HDMI port, that’s not going to work. The laptop’s HDMI port is almost always an output, not an input.
But all hope isn’t lost! There are workarounds using software and network connections to mimic the effect of using your laptop as a second monitor, which we’ll dive into in just a bit.
Why Can’t I Just Plug an HDMI Cable Into My Laptop?
Here’s a common point of confusion: many people think HDMI ports on laptops can act as video inputs. Nope.
- HDMI Out: Sends video from your laptop to an external monitor or TV.
- HDMI In: Receives video signal to display on your device (very rare on laptops).
Most laptops come with HDMI or USB-C ports that only send video signals out, so no direct cable connection to use the laptop as a monitor.
If you want to be sure, check your laptop’s manual or specs sheet. Sometimes, they label ports clearly, but if not, a quick Google search with your laptop model and “input/output ports” will do the trick.
What Are the Technical Requirements and Limitations?
Let’s talk about what you do need to use your laptop as a screen for another device.
1. Software That Enables Screen Sharing
Since direct cable connection won’t work, you need to connect your devices via a network—usually Wi-Fi or Ethernet—and use software that streams the video from one to the other.
2. Both Devices on the Same Network
It’s essential that your laptop and the other device are connected on the same local network. Otherwise, the software won’t be able to find or communicate with each device.
3. Decent Network Speed and Hardware
Because this method streams video over the network, both devices need a decent wireless or wired connection to reduce lag and maximize display quality. Also, the laptop’s CPU and GPU should be able to handle streaming and decoding the video feed smoothly.
4. Limitation: Latency and Image Quality
Streaming video introduces some delay—usually small but noticeable if you’re playing fast-paced games or doing precision work. And depending on the software and your setup, the image quality can degrade a bit compared to a direct cable connection.
Which Software or Hardware Solutions Enable This?
Software Solutions
Here are some popular and beginner-friendly tools that let you use your laptop as a second monitor:
| Software | How It Works | Pros | Cons | Platforms Supported |
|---|---|---|---|---|
| Spacedesk | PC streams video over network to laptop | Free, easy to set up | Some latency, Windows only for server | Windows (server), Windows/iOS/Android (client) |
| Duet Display | Uses USB or Wi-Fi to turn laptop into second display | Low latency, good image quality | Paid app, Mac & Windows only | Windows, macOS, iOS |
| Windows 10/11 Wireless Display | Built-in “Projecting to this PC” feature | No extra software needed | Windows only, sometimes tricky setup | Windows only |
| Deskreen | Uses browser to cast video over Wi-Fi | Free, multi-platform | Requires good network, some latency | Windows, macOS, Linux |
(For Mac users, AirPlay can also be used to mirror or extend displays to compatible devices, but it’s more limited for using the laptop itself as a monitor.)
Hardware Alternatives
If software solutions don’t feel fast or reliable enough, some hardware options exist—but they’re less common and often costly.
Video Capture Cards: You can feed HDMI output from your desktop into a USB capture card connected to your laptop. Your laptop then shows the capture card’s input window, functioning like a monitor. But this method is expensive, adds latency, and the quality depends on the capture card.
Dual-Display Adapters or Docking Stations: Some docking stations allow multiple video inputs and outputs but rarely enable using a laptop as a display for another device.
For most beginners, software solutions are easier and cheaper.
Step-by-Step: How to Use Your Laptop as a Monitor Using Spacedesk (Example)
Let’s get practical. I’ll walk you through setting up Spacedesk, a popular and free app that works on Windows and Android/iOS devices.
What You’ll Need:
- A Windows PC (the device you want to extend or mirror)
- Your laptop (which will act as the second monitor)
- Both devices on the same Wi-Fi network
Step 1: Download and Install Spacedesk
On your main PC (the server), go to spacedesk.net and download the Spacedesk DRIVER software. This allows your PC to send video over the network.
On your laptop (the client), download the Spacedesk VIEWER app from the Microsoft Store or relevant app store.
Step 2: Open Spacedesk Server on Your PC
- Launch the Spacedesk server application on your PC. It will display your PC’s IP address.
Step 3: Connect From Your Laptop
- Open the Spacedesk Viewer app on your laptop.
- Enter the server IP address or select your PC from the list.
- The connection should start, and your laptop will now show an extended or mirrored screen.
Step 4: Adjust Display Settings
- On your main PC, right-click the desktop, select Display settings.
- You’ll see your laptop listed as a second display.
- Choose to extend or duplicate your display depending on your needs.
- Arrange the screens to match their physical layout.
Step 5: Start Using It!
You can drag windows onto your laptop screen as if it were a real external monitor. Keep in mind latency might be noticeable if you move windows fast or play videos.
Addressing Common Pain Points
Confusion About Input vs Output Ports
It’s totally normal to get mixed up. Since most laptops only have video output ports, you can’t plug in your desktop’s HDMI cable directly to your laptop and expect the display to work.
Tip: Look for “HDMI IN” in your specs if you want a direct cable solution—spoiler: it’s rare.
Difficulty Finding Reliable Software
There are many apps, but not all are trustworthy or easy to use. I recommend sticking with apps like Spacedesk or Duet Display, which have been around for years and have solid user reviews.
Performance or Quality Issues
Don’t expect perfect zero-latency performance. Streaming video over Wi-Fi introduces some delay and can reduce image sharpness. If you do a lot of gaming or video editing, this might not be ideal.
To reduce lag:
- Use Ethernet connections on both devices if possible.
- Close unnecessary apps to free up resources.
- Choose apps that support USB connections like Duet Display (if compatible).
FAQ: Quick Answers
| Question | Answer |
|---|---|
| Can I use HDMI cable directly to laptop? | No, laptop HDMI ports are almost always outputs. |
| Can this work with Mac and Windows together? | Some apps support cross-platform, but check compatibility. |
| Does it work for gaming? | Possible, but latency might be noticeable. |
| Is it free? | Apps like Spacedesk and Deskreen have free versions; others like Duet Display are paid. |
| What if my laptop is old? | Older devices might struggle with smooth video streaming. |
Final Thoughts
Using your laptop as a monitor isn’t as simple as plugging in a cable, but it’s definitely doable with the right software and setup. For everyday tasks like browsing, coding, or office work, software streaming solutions work great. But if you want to game or do professional video editing, a dedicated monitor is still the way to go.
Next time you’re stuck with a single screen and wish you had more, try these apps out. It might save you some money and help you be more productive without buying new gear.
References
[1] According to Spacedesk official site, Spacedesk enables your laptop to act as an additional display over the network: https://spacedesk.net
[2] According to Duet Display, their app provides low latency second display functionality over USB and Wi-Fi: https://www.duetdisplay.com
[3] Windows support explains how to use “Projecting to this PC” for wireless display: https://support.microsoft.com/en-us/windows/project-to-wireless-display-3ff7e6fd-5b04-4b43-8f89-69b545674e7f
[4] Deskreen offers a browser-based solution to use any device as a secondary screen: https://deskreen.com
If you try this out and hit any snags, just ask! I’ve been there—getting tech to work together can be a wild ride, but it’s worth it.
Danny Inayat