Fix macOS Catalina Screen Resolution on VirtualBox

One of the most important parts of using an operating system is its screen resolution. When you have a huge screen resolution or even if it’s not huge, it’s definitely bigger than the default screen resolution of the operating system you install. In this case, you would likely wish to experience the complete resolution when you’ve a larger screen. This happens after you install, when you switch to the full-screen resolution mode, wait for a precious wallpaper to cover your entire screen, but instead, the wallpaper remains at the same resolution instead the side screen will be covered will the black screen. It’s really annoying.

If you’ve installed macOS Catalina on VirtualBox and browse a little bit, you may have noticed an important missing thing, the screen resolution, which doesn’t expand when you switch to full-screen mode. Unlike VMware, when you’ve finished the installation, you will install VMware Tools on macOS Catalina which fixes most of the things that one of them is screen resolution. Plus enhances performance, graphics, and video settings. But unfortunately, that’s not applicable here. Don’t worry, there’s another trick to it. Here’s how to fix macOS Catalina screen resolution on VirtualBox.

• Related: Install macOS Catalina on VMware on Windows PC

macOS Catalina Default Screen Resolution

Step One: Switch Off macOS Catalina

First, shut off the virtual machine by clicking on close on the VirtualBox. This is super-important.

Shut Down VM

When the close virtual machine prompts up, click Power off the machine then click OK.

Close Virtual Machine

Step Two: Edit Catalina Screen Resolution Key

At this point, you’ll need a single file of the screen resolution key and modify it for your virtual machine.

For that, you’ll need to download the macOS Catalina Screen Resolution. Once it is with you, open it and replace “macOS Catalina” with your virtual machine. I guess it would be macOS Catalina or only Catalina, in which case, you’ll only need to do a simple edit

cd "C:\Program Files\Oracle\Virtualbox"
VBoxManage setextradata “Your Virtual Machine Name” VBoxInternal2/EfiGraphicsResolution X

1280x7201920x1080 
2048x1080 
2560x1440
3840x2160
1280x800 
1280x1024 
1440x900 
1600x900

VirtualBox doesn't support 1366x768 so you can use 1280x720 with "Scaled Mode".

Next up, modify the screen resolution which is “1920×1080” with the resolutions tested below.

Edit macOS Catalina Screen Resolution

Step Three: Close VirtualBox

While the virtual machine is closed, now you need to exit from VirtualBox. These two are really important to be closed, so make sure they aren’t open. Otherwise, this would probably make the virutal machine unusable.

Close VirtualBox

Step Four: Apply macOS Catalina Screen Resolution

The commands are ready to apply now. The only step to fix macOS Catalina screen resolution is now to apply the commands which are very important.

When you’re done, open Command Prompt without administrator privileges.

Open Command Prompt

On this window, in order to locate the VirtualBox, copy and paste the first line of the command.

Now copy and paste the next line of the command and hit Enter. This will change the default resolution to your desired resolution.

Apply Commands

And there you go! With this simple trick, you’ve fixed the macOS Catalina screen resolution permanently.

Step Five: Switch on macOS Catalina

This should work properly without any issue if you’ve done all the steps correctly.

To try and see everything, switch on the macOS Catalina machine from VirtualBox.

Start Machine

Without you switch to the entire resolution, it will automatically start in your preferred resolution. Simply sign in and you’ll enjoy the perfect resolution.

To experience the seamless resolution, from the top menu, click on View and click on Full-screen Mode. It will perfectly cover your entire screen without a side black cover.

Full-Screen Mode

You’ll see the gorgeous Catalina wallpaper across all across the edge of your screen.

macOS Catalina Screen Resolution Changed

To check, from the top click on the Apple icon and select About This Mac.

About This Mac

From the menu, click on Display tab and the screen resolution will be in front of you.

macOS Mojave Screen Resolution Changed

The resolution will completely fit and there’s no problem at all. If it’s smaller or doesn’t cover your screen, you may change the resolution with the steps we did and change the screen resolution this time. This is the perfect way to enjoy the ideal Mac.