You have a lot of cloud storage options these days, and depending on what hardware you're using, the best option may be a little different for you than me. iPhone/iPad/Mac users may get the most value from iCloud, which is tightly integrated with iOS and macOS, while Android users could find Google Drive is the best, and Windows fans might like OneDrive. And then there's Dropbox, which has been at this the longest and is basically platform agnostic.
Each service has its pros and cons, but I wanted to look at the 4 major storage options from a straight up price comparison. How much storage do you get based on how much cash you throw at them? Here's a visual breakdown:
If you don't want to spend a penny, Google Drive is the winner, as 15GB isn't a ton of storage, but it is substantially more than the paltry 2-5GB the other services give away.
If you're looking to spend just a couple bucks, it's a toss up between iCloud and Google Drive. iCloud's $3 plan is a pretty great deal, as it gets you up to 200GB for basically nothing per month. Meanwhile, Google Drive's $2 plan gets you 100GB, which is also pretty good for basically nothing per month. Both services provide a good amount of online storage for an amount so small you'll probably not even notice it coming out of your bank every month.
Finally, if you want to get the full 1TB of storage every service offers, OneDrive is clearly the best deal. At $7/month, it's 30% less than all the other services. Considering that $7 also gets you full access to Microsoft Office 365, it's easy to see how that could be the best package for a lot of people.
The odd man out in this comparison is Dropbox, which despite being the poster child for cloud storage, is never the best deal. It has the worst free plan, and only has one paid option, which is merely in line with iCloud and Google Drive (and well behind OneDrive).
Which one is best for you? I can't really say, unfortunately. Personally, I use iCloud and OneDrive for my online storage and file sync. I'm on the $1TB OneDrive plan which is where I store all of my critical files, and the $3 iCloud plan which lets me sync my photo library, Desktop, and some miscellaneous files between my devices.