“The speed may vary depending on the type of transferred files — there is, for example, a higher overhead for key generation/decryption for smaller files. As a result, the speed decreases when uploading or downloading numerous smaller files compared to a handful of big ones.

“The download process can be slow, especially if you are downloading a large number of small files (less than 1 MB each). These files need to be downloaded in the background one by one to ensure that each download is successful and the file is properly decrypted. As a result, the download speed cannot exceed a certain threshold since the client only downloads/uploads up to 3–4 files simultaneously.

…If the 4 files being downloaded are 1 KB each, the download speed would be limited due to the small file size and the sequential nature of the process.”

Reading time: 3.5 min

Summary:

• Proton Drive upload and download speeds struggle with many small files.
• Zip into 1 file before you upload/download to speed up.
• Consider Ente instead of Proton Drive if you want end-to-end encrypted photo backups.

Proton Drive Struggles With Lots of Small Files

I tried uploading a large collection of files to Proton