How to Use an iPad or Laptop as a Second Monitor

An iPad Pro as a second display for a MacBook Air with Sidecar. Picture: Apple, from "Use an iPad as a second display for a Mac" [1].

Use an iPad as a second monitor for a Mac (Sidecar)

Check first that your Mac and iPad are on this list [1]:

1. Get both devices ready. Sign in to the same Apple Account on both. Turn on Wi-Fi, Bluetooth and Handoff, and keep them within 30 feet (10 meters) of each other [2].
2. Connect from your Mac. Click Control Center in the menu bar, click Screen Mirroring, then choose your iPad [2]. Or open System Settings > Displays, click the button on the right, then choose your iPad [2].
3. Pick extend or mirror. In Displays, choose your iPad, then use the Use as menu [2]. Extend adds the iPad as more desktop space. Mirror shows your Mac screen on the iPad [1][2].
4. Arrange the screens. Click Arrange and drag the iPad to the side where it sits on your desk [2].
5. Move windows across. Drag a window to the edge of the screen until the pointer appears on the iPad [2].

Wired or wireless? Sidecar works wirelessly. To keep the iPad charged, Apple suggests you connect it to the Mac with the iPad's USB charge cable [1]. Over USB, the iPad must be set to trust your Mac [1].

On the iPad you can type and click with the Mac's keyboard and mouse, and a sidebar gives you the Command, Option, Control and Shift keys. You can also use an Apple Pencil as the pointer [1].

To stop, click Control Center > Screen Mirroring on the Mac and deselect your iPad. Or tap the disconnect button at the bottom of the iPad's sidebar [1][2].

iPad does not show up

Work down this list:

1. Same Apple Account on both devices, with two-factor authentication [1].
2. Wi-Fi and Bluetooth on, on both devices and on the same Wi-Fi network [2]. Handoff must also be on [1].
3. No hotspot. The iPad must not share its cellular connection, and the Mac must not share its internet connection [1].
4. Closer together. Wireless Sidecar needs the devices within 10 meters (30 feet) [1].
5. Check the models in the table above, and install the latest macOS and iPadOS updates [1].
6. Or connect by cable. You can also connect the iPad to the Mac with a USB cable [2]. The iPad must be set to trust your Mac [1].

Use an iPad as a second monitor for a Windows PC

Sidecar works only between a Mac and an iPad [1]. On a Windows PC you need a third-party app. Two that say they support it on their own sites:

Install the PC part on the computer and the app on the iPad [4][5]. spacedesk says its extra screens can mirror one screen or extend the desktop [5]. We have not tested these apps ourselves. Check each maker's site for the current price and setup steps.

Use a laptop as a second monitor

A spare Windows 11 laptop can be a wireless second screen for another Windows PC, with Microsoft's optional Wireless Display feature [3].

On the laptop (the one that becomes the screen):

1. Open Start > Settings > System > Projecting to this PC [3].
2. Add Wireless Display. Under Add the "Wireless Display" optional feature to project to this PC, select Optional features. Select View features, type "wireless display", tick it, then select Next and Install [3].
3. Open the Wireless Display app. Type "wireless display" in the search box on the taskbar and select it [3].

This is the page you see in step 1 before the feature is installed:

On your main PC:

1. Press Windows key + K and select the laptop [3].
2. Choose what each screen shows. Press Windows key + P. Extend spreads your desktop across the screens; Duplicate shows the same thing on both [3].

If the main PC does not list the laptop, check that the laptop has Wi-Fi on and the Wireless Display app open [3]. The app needs Windows 11, version 22H2 or later. Earlier versions use the Connect app [3]. The spacedesk Viewer also runs on Windows laptops, over your local network [5].

When an iPad is too small

If you would rather have a fixed second screen on your desk than an iPad, Owl3D makes the Owl3D Shift. It is a 14-inch 4K screen meant to sit beside a laptop or desktop [6]. Over USB-C or Mini-HDMI it works as an ordinary 4K 2D monitor with most computers, without the Owl3D app [6]. With the Owl3D app it also shows movies, games and photos in glasses-free 3D. The 3D needs a computer that meets the requirements on the Shift page [6].

This guide is about using an iPad or laptop as a screen for a computer. It does not cover showing the iPad's own screen on a Mac.

Frequently asked questions

Can you use an iPad as a second monitor?

Yes. For a Mac, use Sidecar, which is built in [1]. For a Windows PC, use an app such as Duet or spacedesk [4][5].

Do I need an app for Sidecar?

No. You set it up on the Mac, in System Settings > Displays or the Screen Mirroring menu [1][2]. Your Mac and iPad must be on Apple's list of supported models [1].

Can I use my iPad as a second monitor without Wi-Fi?

Apple does not say so directly. It lists Wi-Fi, Bluetooth and Handoff as requirements only for wireless Sidecar. Over a USB cable, the iPad must be set to trust your Mac [1]. But Apple's setup steps ask for Wi-Fi, Bluetooth and Handoff on both devices before you begin [2].

Can I use my iPad as a second monitor for a Windows laptop?

Yes, with an app. Sidecar does not work with Windows [1]. Duet and spacedesk both have a Windows part and an iPad app [4][5].