It's under Admin -> General Configuration -> Attachment Settings.
I'm not sure you can change it in OnDemand, and you should also be aware that Confluence isn't really designed for very large files, so if you're thinking of uploading a lot of data, you might struggle.
Hello Community 👋🏼 I’m Makisa, a product manager on Confluence Server and Data Center. Confluence Server & Data Center 7.0, our latest platform release, is now available and we wanted to shar...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events