There are many online storage providers provide free storage services for personal. Here I picked out the best free online storage, I hope these can help you.
Box gives you 10 GB secure storage with 250 MB file upload size for free and lets you organize your files into folders in the cloud, just like you would on your desktop. You can share links or entire file folders with others and see when they've been viewed.
Dropbox is a secure place to keep photos, documents, and videos that you can access from your computer, smartphone, or tablet. You can share the files with your social networks as well. Dropbox for free user: 2 GB of space Safe, reliable backup, Access from anywhere, Simple file sharing.
You have 15 GB of free storage to share across Google Drive, Gmail, and Google+ Photos. If you use Google Apps at work or school, you have at least 30 GB of storage. While you may have a lot of files and folders in your Google Drive, only items that you've synced or uploaded use storage space. Google Docs, Sheets, or Slides or items shared with you don’t count toward your storage space.
Microsoft OneDrive for free user: 15 GB secure storage, earn an extra 15 GB of storage when you backup your camera roll, refer a friend to OneDrive and both of you will get an extra 500 MB (maximum 5 GB).