What is the best free cloud storage?
MEGA gives the most free space of any mainstream provider at 20 GB, with end-to-end encryption included. pCloud and Icedrive offer around 10 GB free with nicer apps, and Filen pairs 10 GB with open-source, zero-knowledge encryption.
Free tiers are marketing, but that does not make them useless; it makes them comparable. MEGA's 20 GB is the headline number of the category and comes with end-to-end encryption by default, making it the rational first stop for anyone parking a meaningful archive for free. The apps are functional rather than beautiful, and speeds can be throttled at peak times, which is the price of free at that scale.
The 10 GB tier is where quality lives: pCloud's free plan is the same fast, polished product as its paid one, Icedrive's clean interface makes it the nicest free drive to actually use, and Filen offers open-source zero-knowledge encryption, rare at any price, let alone free. Koofr's smaller free plan has a unique trick: it connects your existing Google, Dropbox, and OneDrive accounts into one searchable view.
Two realities to respect: free accounts sometimes expire with inactivity (log in a couple of times a year), and nothing irreplaceable should live in only one free account, because support and guarantees are what you are not paying for. Free tiers are excellent overflow and trial space; family photos deserve a paid home with versioning.