The individual file size limit for uploads to Online Storage is 2GB. The total upload limit for your account depends on your plan. To view the available space for your plan, look below the Advanced Search and Upgrade links in the upper-left corner. You cannot upload files that exceed the available space in your Online Storage plan.
You can upload multiple files or folders at once. However, you cannot upload more than 100,000 total items (including files and/or folders), within any single directory or folder, in your Online Storage account. Keep in mind, if you upload a large number of files at one time, the upload may take several minutes to complete.