Catalina To Usb

How to make a bootable ISO of macOS Catalina


Similar to Mojave, if you can get it to install and boot, sure, there is no reason you can't -run- Catalina from an external USB-C drive. Given the hiccups involved w/Mojave, however, I'd not bother. If you need to include an external, try parking your Home folder on it, instead, and use FUS to get in.

Catalina Usb Maker

I’m not kidding, forget about the mess below. Apple has updated and documented this across several macOS versions. Find it at’s article “How to create a bootable installer for macOS“

How To Create macOS Catalina Bootable USB on Windows: Step by Step This is a 4 step process, so please make sure you do not skip any part of it and eventually get frustrated with the failure. I have also shared a complete video tutorial on How To Create macOS Catalina Bootable USB on Windows: Step by Step, you can find the video at the end of. MacOS Catalina 10.15.5 introduces battery health management in the Energy Saver settings for notebooks, an option to control automatic prominence of video tiles on Group FaceTime calls, and controls to fine-tune the built-in calibration of your Pro Display XDR. The update also improves the stability, reliability, and security of your Mac. Bootable USB installers offer an easy way to upgrade multiple Macs to macOS Catalina, to perform clean installs of MacOS Catalina, to perform maintenance from a boot disk like formatting disks, modifying disk partitions, and performing restorations, and much more. We’ll walk through how to create a boot USB install drive for MacOS Catalina 10.15. Here’s how you can create it. Make sure the USB drive is at least 8GB in size, and nothing else is stored on it. Download the macOS Catalina installation file using this link. Turn off the Mac and then insert the bootable USB drive. Now turn the Mac back on while holding the Option key. It will take you to the boot menu where you can select.

Ignore everything below!!!

I previously wrote up my version of creating a macOS Mojave and Sierra HERE and HERE.

Catalina To Usb

I’m updating it for macOS Catalina 10.15

CatalinaBurn catalina to usb

First, navigate to the macOS Download page in the App Store and choose “GET”. Depending on whethere there’s a local copy or not, you may have to choose “Download” if you are offered it, and wait to download the whole installation app.

When you are done, the Installer will open. Quit the installer (via menu or via command-Q). This will leave the “Install macOS Catalina” installer in your /Applications folder.

Then copy this code and save it as a shell script named “”

After creating the shell script, you can make it executable (“chmod +x”) or just run it like “sh”. If you aren’t proficient in running scripts, you probably shouldn’t be messing with this in the first place!

You want to be sure to run this code in a directory that has enough space to hold a few copies of the ~10GB ISO simultaneously. Ideally it’s on fast media as well. And also not part of your cloud storage (iCloud Desktop, Dropbox, etc.). Often your home directory is just fine.

Bootable USB?

CatalinaCatalina usb wifi

Burn Catalina Iso To Usb

Want a bootable USB? Simply use dd to copy the ISO directly to your USB drive. I am not going to give you a real command to copy to do that… dd can be dangerous. But it’s as simple as something like this:

sudo dd if=Catalina.iso of=/dev/rdisk### bs=4m

Boot Catalina To Usb

Good luck!