The Bodleian Library in Oxford and the Folger Shakespeare Library in Washington DC are to put all 75 editions of William Shakespeare's plays from before 1641 online.
The quartos are the earliest printed editions of the plays and are the closest to what Shakespeare actually wrote still in existence.
The project is intended to give the public greater acccess to the plays and downloading of the quartos will begin next month.
Online users will be able to compare and study the texts, which are the earliest sources for the 37 plays Shakespeare is known to have written.
"There will be countless new ways for scholars, teachers, and students to examine the quarto texts, particularly of 'Hamlet'," Folger library director Gail Kern Paster told Reuters.
"You find out all sorts of things - about how the copies went through the press, and also about the printing process," she added.
