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.
Find out 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 may 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.
OS X has evolved throughout the years. Leopard was a great OS and now Snow Leopard tweaks all the features and polishes it up. I am very much happy to own S.L. This disc installs great on my Mac and PC. A define purchase for those first generation Intel Macs.
- Like Lion (OS X 10.7) before it, Mountain Lion (OS X 10.8) doesn't ship on a disc—it's available only as an installer app downloadable from the Mac App Store, and that installer doesn't.
- Hold down the 'Command' and 'R' keys while your Mac is booting. This will allow you to select one.
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. Find out 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 being downloaded 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 may 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 finish without putting your Mac to sleep or closing its lid. Your Mac may restart, show a progress bar or show a blank screen several times while macOS and related firmware updates are being installed.
Learn more
You may 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.
Mac Os X Price
Upgrading to Snow Leopard, Lion, or Mountain Lion
You can upgrade directly from Snow Leopard to Mountain Lion provided your computer is able to run Mountain Lion. Be sure to check that information in the Mountain Lion section below.
Upgrading to Snow Leopard
You can purchase Snow Leopard by contacting Customer Service: Contacting Apple for support and service - this includes international calling numbers. The price is $19.99 plus tax. You will receive physical media - DVD - by mail.
Install macOS
Follow the onscreen instructions in the installer. It may 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 finish without putting your Mac to sleep or closing its lid. Your Mac may restart, show a progress bar or show a blank screen several times while macOS and related firmware updates are being installed.
Learn more
You may 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.
Mac Os X Price
Upgrading to Snow Leopard, Lion, or Mountain Lion
You can upgrade directly from Snow Leopard to Mountain Lion provided your computer is able to run Mountain Lion. Be sure to check that information in the Mountain Lion section below.
Upgrading to Snow Leopard
You can purchase Snow Leopard by contacting Customer Service: Contacting Apple for support and service - this includes international calling numbers. The price is $19.99 plus tax. You will receive physical media - DVD - by mail.
Third-party sources for Snow Leopard are:
After you install Snow Leopard you will have to download and install the Mac OS X 10.6.8 Update Combo v1.1 to update Snow Leopard to 10.6.8 and give you access to the App Store.
Before upgrading check that you computer meets the minimum requirements: How to make a disk image mac.
Mac Os X Lion Dmg
Snow Leopard General requirements
1. Mac computer with an Intel processor
2. 1GB of memory
3. 5GB of available disk space
4. DVD drive for installation
5. Some features require a compatible Internet service provider; fees may
apply.
6. Some features require Apple's MobileMe service; fees and terms apply.
Upgrading to Lion
First, you need to upgrade to Snow Leopard 10.6.8 as stated above.
You can purchase Lion by contacting Customer Service: Contacting Apple for support and service - this includes international calling numbers. The cost is $19.99 (as it was before) plus tax. It's a download. You will get an email containing a redemption code that you then use at the Mac App Store to download Lion. Save a copy of that installer to your Downloads folder because the installer deletes itself at the end of the installation.
Before upgrading check that you computer meets the minimum requirements:
Lion System Requirements
1. Mac computer with an Intel Core 2 Duo, Core i3, Core i5, Core i7, or
Xeon processor
2. 2GB of memory
3. OS X v10.6.6 or later (v10.6.8 recommended)
4. 7GB of available space
5. Some features require an Apple ID; terms apply.
Upgrading to Mountain Lion
Be sure your computer meets the minimum requirements:
Macs that can be upgraded to OS X Mountain Lion
1. iMac (Mid 2007 or newer)
2. MacBook (Late 2008 Aluminum, or Early 2009 or newer)
3. MacBook Pro (Mid/Late 2007 or newer)
4. MacBook Air (Late 2008 or newer)
5. Mac mini (Early 2009 or newer)
6. Mac Pro (Early 2008 or newer)
7. Xserve (Early 2009)
Mac Os X Lion 10.7.5
Are my applications compatible?
See App Compatibility Table - RoaringApps - App compatibility and feature support for OS X & iOS.
Mac Os X Lion Mac App
Am I eligible for the free upgrade?
See Apple - Free OS X Mountain Lion upgrade Program.
For a complete How-To introduction from Apple see Apple - Upgrade your Mac to OS X Mountain Lion.
Nov 18, 2012 1:38 PM
