Download Macos Catalina Offline Installer

Attempting to download macOS Catalina from the Mac App Store you may find that a small version of the “Install macOS Catalina.app” file downloads to the “Applications” folder, rather than the complete 8.1 GB installer file.

The tiny (just tens of megabytes) incomplete installer requires an internet connection during usage to download the rest of the Catalina update files. Additionally, it does not allow to create a macOS Catalina USB installer drive for use on multiple computers.

In this tutorial, I’ll show you how to download the complete “Install macOS Catalina.app” file from Apple server using the “macOS Catalina Patcher” app instead of via the Mac App Store.

A similar mini-installer issue occurred previously with some users getting a tiny incomplete macOS High Sierra installer and macOS Mojave installer too and I covered a similar workaround here and here to download the complete installer file from Apple server.

About the app

If you are Mac user and wants to experience all new features and functions of latest macOS Catalina 10.15.7 Final Update then you can instantly 'Free Upgrade' to latest version from App Store or you can free Download macOS 10.15.7.DMG Final Installer Without App Store from this post for offline installation on multiple Mac devices. How to create a macOS Catalina installer. 1) Download the Install macOS Catalina application from the Mac App Store. If you want to download a Beta version instead, the process is slightly different: Paid developers can download the Beta Access Utility from the Apple Developer portal downloads section. Once installed on your computer, it will. Download macOS Catalina 10.15.2 (19C57) free latest version offline DMG image installer. MacOS Catalina 10.15.2 (19C57) is a powerful macOS release providing numerous enhancements and a stable.

In this workaround, we’re going to use the macOS Catalina Patcher app from the dosdude1.com. This app is intended for those with unsupported Macs and Hackintosh users, but any Mac user can use the app to be able to download the complete macOS Catalina installer file from Apple server. For our purposes in this particular walkthrough, we will use the app only to download the complete installer file.

Note! This method relies on a third party app from an unverified third party source. If you are not comfortable with using unvetted and unverified software, do not follow this process.

Let’s begin

Downloading the complete “Install macOS Catalina.app” file from Apple server using the “macOS Catalina Patcher” app is a really easy process. Now, step by step guide.

Go to the official website of the “macOS Catalina Patcher” app here and download the app.

The download link is labeled as “Download Latest Version” on that page.

Installer

Launch the “macOS Catalina Patcher” app.

Note! By default, macOS preventing apps from unidentified developers or sources from being launched. So you most likely will get an alert message that says: “macOS Catalina Patcher.app can’t be opened because it is from an unidentified developer”. To allow just one specific app to run do the following:

Download Macos Catalina Full Installer

  1. Hold down the Control key and click the app icon. From the contextual menu choose Open.
  2. A popup will appear asking you to confirm this action. Click the Open button.

Click the “Continue” button, and then select “Download a Copy”.

Confirm that you want to download the “Install macOS Catalina.app” app to start the download to your hard drive.

Close the “macOS Catalina Patcher” app when the download is complete and locate the “Install macOS Catalina.app” file you downloaded.

Download Macos Catalina Dmg Offline Installer

Note! The download will be completed when you are prompted to choose an installation method. See the screenshot below.

Conclusion

That’s it, you’re done. Now you have the complete “Install macOS Catalina.app” file downloaded. So simple isn’t it?

You can confirm that you have the complete “Install macOS Catalina.app” file by getting info on the file. For this simply select the file and click the Spacebar key (or right-click on the file and choose “Get Info”). The complete installer should be around 8.1 GB rather than the tiny (just tens of megabytes) incomplete installer that requires additional downloads.

Note! Remember, the “Install macOS Catalina.app” file deletes itself automatically after macOS Catalina has successfully installed. Therefore, you may want to make a backup by having previously copied it to external storage.

Let me know in the comments section if you know another way to download the complete “Install macOS Catalina.app” file rather than the tiny incomplete installer.

I hope this article has helped you learn how to downloaded the complete “Install macOS Catalina.app” file from Apple server. If this article has helped you then please leave a comment

Thanks for reading!

Arthur is a designer and full stack software engineer. He is the founder of Space X-Chimp and the blog My Cyber Universe. His personal website can be found at arthurgareginyan.com.

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Customers get Software upgrades for Mac computers through the online app store ever since the release of macOS Lion. Be it a clean install or upgrade, Mac App store require you connect to the internet to download whole installation files. The online OS update is OK if you have stable broadband connectivity and enough bandwidth. Apple also provides an option for internet recovery of macOS if your computer fails to boot. But there are situations where you can’t download the OS from the Apple servers. Having a macOS offline installer or a bootable USB disk is the only solution in such scenarios.

Download macOS offline Installer

Installing macOS without internet requires a bootable USB disk. And you need to download a full-size macOS installer for making this disk. Hence, before anything, we will tell you how to download macOS offline installer directly from Apple to your Mac using a GitHub script.

Download the gibMacOS script from this link and extract it to your Mac. From the extracted folder, run the script called gibMacOS.command — it will open the Terminal as shown below.

Wait for the script to fetch the macOS download catalogue from Apple. When the list is ready choose a number as per your OS option and press the Return/Enter key. You can use this script to download macOS Big Sur (11.1), Catalina (10.15), Mojave (10.14), and High Sierra (10.13.6). A new folder “macOS downloads” appears in the “gibMacOS-master” as you provide a download option, and the OS starts downloading as you can see in the video.

Installer

The OS gets downloaded as parts, PKGs, DMGs and other files. For macOS versions up-to Big Sur, you need to use another script “BuildmacOSInstallApp.command” in the main folder to join all the downloads and make the full macOS installer app. All you need is to drag and drop the downloaded macOS folder to the terminal window. The script will build the offline installer and save it to the same folder.

You don’t need to use the second script if your choice is macOS Big Sur. Because, for macOS Big Sur you get a full-size installer from Apple in PKG format. Double-click and open the InstallAssistant.PKG to save the “Install macOS Big Sur.app” to the Applications folder.

Apart from this, some older versions of macOS are available for direct download from Apple (Sierra, EL Capitan, Yosemite) in DMG format.

How to make a macOS bootable USB installer

It is possible to create a backup macOS installer on a DVD or USB drive but later is the best choice. Most of the Macs these days don’t have DVD slots, and the installation through a disc is very slow. Hence we discuss only about making macOS recovery installer on a USB disc. For this you need a Mac and a USB pen drive of at least 8 GB space, and a third-party app called DiskMaker.

Download macos catalina offline installer windows 10
  1. First, download a copy of Disk Maker from the official website.
  2. Choose a version as per your requirement. For example, if you want make USB installer for macOS Catalina 10.15, download Disk Maker X 9.
  3. I use an MacBook Pro with High Sierra. Hence, I’m downloading disk maker X 7.
  4. The next step is to download full macOS installer from the App Store to your Applications folder.
  5. Run Disk Maker DMG installer and copy the app to the Applications.
  6. The application will automatically detect the downloaded macOS as shown in the screenshot. Select “Use this Copy” if you would like to proceed with it.
  7. Next is setting the USB pen drive for creating the bootable installer. Choose the third option ” An 8 GB USB Thumb drive.”
  8. The app will list all drives in your system. Pick the one you would like use as macOS USB installer.
  9. Ignore the warning message and proceed to Erase and Create macOS USB disk. Don’t forget to provide your admin password when it prompts.
  10. Keep checking notifications tab for progress. When it completes you will find Install macOS Mojave (or High Sierra) mounted to your desktop as a USB disk.
  11. That’s your backup. Unmount and keep the USB installer to a safe place.


Unfortunately, the above app is not compatible with macOS Big Sur 11 and above. Check the instructions on Apple website, the manual method to make macOS offline USB installer.

What is the alternative if I don’t have usable Mac at the moment?

This method is applicable when you have a Mac, and the internet recovery fails. But think about a situation when your only Mac stops to boot, and you don’t have USB installer or TimeMachine backup! Downloading MacOS DMG file might save you. If you have a macOS DMG, you can create bootable USB disk from a Windows PC — use a software like TransMac for this purpose.

Clean installing or restoring a Mac offline with USB pen drive

Download Macos Catalina Offline Installer

As said earlier, you could use the macOS USB installer to do a clean install or restore it upon a boot failure. Just connect the USB disk and press the Option/Alt Key when you hear the boot sound. The Mac will then display all the startup disks available.

Pick the USB drive starting with the label “Install macOS” and follow on-screen instructions to complete the installation. If you need, use the Disk Utility to format the drive for doing a clean install.