Is there a size limit on files uploaded to Dropbox, Amazon S3, etc.?

Yes, the file size limits are as follows:

1. Dropbox – 350 GB;
2. Google Drive – 5 TB;
3. Amazon S3 – 5 TB;
4. Microsoft OneDrive – 250 GB;
5. WebDAV servers – depends on the server settings (usually 50 MB);
6. FTP and SFTP servers – depends on the server settings.
7. Box – depends on the type of account:
   • 250 MB – Free Personal account;
   • 2GB – Starter;
   • 5GB – Business/Enterprise account.