Is it possible to update my late 2013 iMac to macOS Sonoma?

No, the computer is too old for Sonoma. If you want or need Sonoma then it is time to replace your 11 (almost 12) year old iMac.

macOS Sonoma is compatible with these computers - Apple Support

If you decide to. upgrade to a new computer or just want to get rid of the 2013 iMac you can recycle it for free, to get started please click the following link:

Apple Recycling Programs

As rkaufmann87 has posted, your 2013 iMac cannot be upgraded to macOS Sonoma.

The newest version that it can run is macOS 10.15.7 Catalina.

Though you can't upgrade the machine's OS, you can still use it productively. You can continue to run any of the software that is installed. It can still be used for your music, photos and video libraries, email, games and other entertainment, word processing, calendar functions, etc.

You will probably find that internet access becomes more and more problematic because the browsers are no longer supported and updated, but the computer will continue to do its thing until it doesn't.

Catalina is too old to run current software from Microsoft and Adobe. They have a policy of only supporting the three most recent versions of macOS.

It is recent enough to run the current versions of

• Firefox
• LibreOffice
• The commercial Affinity v2 applications (Photo, Designer, Publisher)
• Some other photo programs like GIMP and GraphicConverter 12

which could help you to extend the useful life of the machine if you need these types of productivity applications.

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