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.

As it says in the title it is a macbook Air, specifically 13 inch early 2015. I have the OS X El Capitan on it now and there is no software update available, and hasn't been for a while. I tried to research online, and I can see that even though it isn't visible it is still possible to update the software.

1. The last update for OS X El Capitan was in July 2018, and Carnegie Mellon University confirmed that El Capitan’s end of life date was August 2018. Snow Leopard Myth I know that some users on forums believe that the best OS version for Macs was Snow Leopard.
2. The Steps for Upgrading to Mac OS X El 10.11 Capitan. The following is steps for upgrading to Mac OS X 10.11 Capitan: Visit the Mac App Store. Locate the OS X El Capitan Page. Click the Download button. Follow the simple instructions to complete the upgrade. For users without broadband access, the upgrade is available at the local Apple store.
3. I just managed to install El Capitan without a hitch on the second attempt. I did run Apple Hardware Dianostics, but no problems were detected. This time round I unplugged every external device - USB hub, monitor, Time Machine etc. Don't know if that made the difference though. – Richard Cosgrove Oct 2.
4. 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.

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.

Mac Os X El Capitan Upgrade To Catalina

• 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.

Apple El Capitan

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

Mac Os X El Capitan Update To Sierra

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.