If you're using macOS Mojave or later, choose Apple menu System Preferences, then click Software Update. If you're using an earlier macOS, use the App Store instead. Learn how to download and install macOS Big Sur Go to the App Store. OS X 10.8 Mountain Lion will be offered exclusively through the App Store, familiar territory for Apple since OS X Lion was provided the same way. Thankfully it's still possible to create a bootable OS X 10.8 Mountain Lion installer from any USB drive, be it a flash key or external hard drive.
To get the latest features and maintain the security, stability, compatibility and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.
Learn how to upgrade to macOS Big Sur, the latest version of macOS.
Check compatibility
If a macOS installer can't be used on your Mac, the installer will let you know. For example, it might say that it's too old to be opened on this version of macOS, or that your Mac doesn't have enough free storage space for the installation.
To confirm compatibility before downloading, check the minimum requirements for macOS Catalina, Mojave, High Sierra, Sierra, El Capitan or Yosemite. You can also find compatibility information on the product-ID page for MacBook Pro, MacBook Air, MacBook, iMac, Mac mini or Mac Pro.
Make a backup
Before installing, it's a good idea to back up your Mac. Time Machine makes it simple, and other backup methods are also available. Learn how to back up your Mac.
Download macOS
It takes time to download and install macOS, so make sure you're plugged into AC power and have a reliable internet connection.
Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.
- macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite or Mavericks
- macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks or Mountain Lion
- macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks or Mountain Lion
Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to start installing the operating system.
- macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion or Lion
- OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion or Snow Leopard
- OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion or Snow Leopard
Install macOS
Follow the onscreen instructions in the installer. It might be easiest to start the installation in the evening so that it can be completed overnight, if needed.
If the installer asks for permission to install a helper tool, enter the administrator name and password that you use to log in to your Mac, then click Add Helper.
Please allow the installation to be completed without putting your Mac to sleep or closing its lid. Your Mac might restart, show a progress bar or show a blank screen several times while it installs macOS and related firmware updates.
Learn more
You might also be able to use macOS Recovery to reinstall the macOS you're using now, upgrade to the latest compatible macOS or install the macOS that came with your Mac.
Upgrade to macOS Big Sur
Before installing this upgrade, make sure that your Mac is ready.
Check compatibility
macOS Big Sur supports most Mac models introduced in 2013 and later.
View compatible Mac modelsMake a backup
Before you upgrade, make a complete backup with Time Machine, or store your files in iCloud.
Learn how to back up your MacFree up space
If the installer needs more storage space to upgrade, you can free up space using tools that come with your Mac.
Free up storage spaceDownload macOS Big Sur
If you're using macOS Mojave or later, choose Apple menu > System Preferences, then click Software Update. If you're using an earlier macOS, use the App Store instead.
Learn how to download and install macOS Big SurGo to the App StoreGet to know macOS Big Sur
Learn about some of the new features of macOS Big Sur.
Control Center
Control Center brings favorite controls such as Bluetooth, Wi-Fi, Do Not Disturb, and Sound together in a single place—so you can easily adjust them at any time.
Use Control CenterNotification Center
Notification Center puts notifications and>
Safari
Customize your start page, navigate with ease using the new tab bar, and access a new privacy report to see just how Safari protects your privacy as you browse.
Get to know SafariMaps
Discover great places around the world and navigate easier with guides, cycling directions, indoor maps, Look Around, electric vehicle routing, and more.
Messages
Send messages to friends and family using new tools that make it easier to keep track of group conversations and give you fun, engaging ways to express yourself.
Use Messages
Learn how to upgrade to macOS Big Sur, the latest version of macOS.
Check compatibility
If a macOS installer can't be used on your Mac, the installer will let you know. For example, it might say that it's too old to be opened on this version of macOS, or that your Mac doesn't have enough free storage space for the installation.
To confirm compatibility before downloading, check the minimum requirements for macOS Catalina, Mojave, High Sierra, Sierra, El Capitan or Yosemite. You can also find compatibility information on the product-ID page for MacBook Pro, MacBook Air, MacBook, iMac, Mac mini or Mac Pro.
Make a backup
Before installing, it's a good idea to back up your Mac. Time Machine makes it simple, and other backup methods are also available. Learn how to back up your Mac.
Download macOS
It takes time to download and install macOS, so make sure you're plugged into AC power and have a reliable internet connection.
Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.
- macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite or Mavericks
- macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks or Mountain Lion
- macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks or Mountain Lion
Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to start installing the operating system.
- macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion or Lion
- OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion or Snow Leopard
- OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion or Snow Leopard
Install macOS
Follow the onscreen instructions in the installer. It might be easiest to start the installation in the evening so that it can be completed overnight, if needed.
If the installer asks for permission to install a helper tool, enter the administrator name and password that you use to log in to your Mac, then click Add Helper.
Please allow the installation to be completed without putting your Mac to sleep or closing its lid. Your Mac might restart, show a progress bar or show a blank screen several times while it installs macOS and related firmware updates.
Learn more
You might also be able to use macOS Recovery to reinstall the macOS you're using now, upgrade to the latest compatible macOS or install the macOS that came with your Mac.
Upgrade to macOS Big Sur
Before installing this upgrade, make sure that your Mac is ready.
Check compatibility
macOS Big Sur supports most Mac models introduced in 2013 and later.
View compatible Mac modelsMake a backup
Before you upgrade, make a complete backup with Time Machine, or store your files in iCloud.
Learn how to back up your MacFree up space
If the installer needs more storage space to upgrade, you can free up space using tools that come with your Mac.
Free up storage spaceDownload macOS Big Sur
If you're using macOS Mojave or later, choose Apple menu > System Preferences, then click Software Update. If you're using an earlier macOS, use the App Store instead.
Learn how to download and install macOS Big SurGo to the App StoreGet to know macOS Big Sur
Learn about some of the new features of macOS Big Sur.
Control Center
Control Center brings favorite controls such as Bluetooth, Wi-Fi, Do Not Disturb, and Sound together in a single place—so you can easily adjust them at any time.
Use Control CenterNotification Center
Notification Center puts notifications and>
Safari
Customize your start page, navigate with ease using the new tab bar, and access a new privacy report to see just how Safari protects your privacy as you browse.
Get to know SafariMaps
Discover great places around the world and navigate easier with guides, cycling directions, indoor maps, Look Around, electric vehicle routing, and more.
Messages
Send messages to friends and family using new tools that make it easier to keep track of group conversations and give you fun, engaging ways to express yourself.
Use MessagesLearn more on YouTubePhotos
Use the expanded editing capabilities in Photos to easily make simple changes and more advanced adjustments to your photos.
Learn how to edit your photosHave a question?
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