12.5GB (from OS X El Capitan 10.11.5 or later) to 18.5GB (from earlier versions). Clean Install: At least 20GB of available space. Compatible Models: MacBook: Early 2015 or newer. MacBook Air/Pro: Mid 2012 or newer. Mac mini / iMac: Late 2012 or newer. Mac Pro: Late 2013 or newer. 2. Official Download Methods
If you're on a compatible Mac (running macOS Sierra 10.12.6 or later), you can use the official Mac App Store link:
If your goal in downloading the DMG file is to fix an unbootable Mac or complete a clean installation, you can flash those image contents to a physical flash drive. Parameter Requirement Minimum Specification 16 GB minimum volume space Format Map Configuration GUID Partition Map File System Type Mac OS Extended (Journaled) Insert your blank flash drive into your computer.
Open the Terminal app and paste the following command to download the latest Catalina installer directly from Apple's servers: softwareupdate --fetch-full-installer --full-installer-version 10.15.7 3. Creating a Bootable DMG/USB
For users seeking the absolute latest security patches, note that Apple has released subsequent updates (effectively 10.15.8) that extend certificate validations. While the 10.15.7 DMG remains the foundational installer, be sure to install all available security updates after completing your initial installation.
| Problem | Possible Cause & Solution | | :--- | :--- | | | This often occurs due to an expired certificate. Solution : Disconnect your Mac from the internet, set the system date back to a time when Catalina was current (e.g., 2019), and then run the installer. | | Cannot install because it's from an unidentified developer | Your security settings are blocking the installer. Solution : Go to System Preferences > Security & Privacy > General and click "Open Anyway" next to the blocked message. | | macOS cannot be installed on this computer (or Volume) | Your Mac model or the disk format may be incompatible. Solution : Ensure your Mac is on the compatible models list above. If installing on an external drive, ensure it is formatted as APFS or Mac OS Extended (Journaled) . |
When asked to confirm that you want to erase the volume, type Y and press .
Keep the USB drive connected. Restart your machine and hold the key down immediately upon boot to select your new installer disk. System Compatibility Matrix
Replace /Volumes/MyVolume with the path to your USB drive.
Do not download Catalina installers from untrusted third-party websites.
12.5GB (from OS X El Capitan 10.11.5 or later) to 18.5GB (from earlier versions). Clean Install: At least 20GB of available space. Compatible Models: MacBook: Early 2015 or newer. MacBook Air/Pro: Mid 2012 or newer. Mac mini / iMac: Late 2012 or newer. Mac Pro: Late 2013 or newer. 2. Official Download Methods
If you're on a compatible Mac (running macOS Sierra 10.12.6 or later), you can use the official Mac App Store link:
If your goal in downloading the DMG file is to fix an unbootable Mac or complete a clean installation, you can flash those image contents to a physical flash drive. Parameter Requirement Minimum Specification 16 GB minimum volume space Format Map Configuration GUID Partition Map File System Type Mac OS Extended (Journaled) Insert your blank flash drive into your computer. Download Macos Catalina 10.15.7 Dmg File
Open the Terminal app and paste the following command to download the latest Catalina installer directly from Apple's servers: softwareupdate --fetch-full-installer --full-installer-version 10.15.7 3. Creating a Bootable DMG/USB
For users seeking the absolute latest security patches, note that Apple has released subsequent updates (effectively 10.15.8) that extend certificate validations. While the 10.15.7 DMG remains the foundational installer, be sure to install all available security updates after completing your initial installation. MacBook Air/Pro: Mid 2012 or newer
| Problem | Possible Cause & Solution | | :--- | :--- | | | This often occurs due to an expired certificate. Solution : Disconnect your Mac from the internet, set the system date back to a time when Catalina was current (e.g., 2019), and then run the installer. | | Cannot install because it's from an unidentified developer | Your security settings are blocking the installer. Solution : Go to System Preferences > Security & Privacy > General and click "Open Anyway" next to the blocked message. | | macOS cannot be installed on this computer (or Volume) | Your Mac model or the disk format may be incompatible. Solution : Ensure your Mac is on the compatible models list above. If installing on an external drive, ensure it is formatted as APFS or Mac OS Extended (Journaled) . |
When asked to confirm that you want to erase the volume, type Y and press . If installing on an external drive
Keep the USB drive connected. Restart your machine and hold the key down immediately upon boot to select your new installer disk. System Compatibility Matrix
Replace /Volumes/MyVolume with the path to your USB drive.
Do not download Catalina installers from untrusted third-party websites.