It's easy to upload any existing PDF articles into ReadCube Papers library. You can simply drag and drop PDF files directly into your ReadCube Papers screen. You can also click the "Add" then "Add Files" (top left corner next to the search bar) and select PDFs from your desktop. 

Screenshot on where to manually import PDFs into ReadCube Papers library.

You can also drag and drop single or multiple PDFs from your computer directly into your ReadCube Papers library.

This video will also walk you through the process.

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Importing from other reference managers

Easy importing with our browser extensions