- Directory of Open Access Books (https://www.doabooks.org/)
- 28302 Academic peer-reviewed books from 381 publisher
Project Gutenberg (https://www.gutenberg.org/)
- Oldest producer of free e-books.
- It is the first and largest single collection of free e-books.
- Collection consists of more than 60,000 e-books.
HathiTrust Digital Library (https://www.hathitrust.org/)
- A collaborative electronic book repository supported by 60 academic and research libraries.
- It provides access to books, serials, standards, theses, etc..
Authorama Public Domain Books (Fictions) (http://www.authorama.com/)
- Free e-books from variety of different authors available to read online or offline.
PDF Drive (https://www.pdfdrive.com/)
- It is a search engine for PDF Files.
- Updated every minute and adding more than 50 books per minute.
- provide students with free textbooks written by professors from the world’s top universities, covering topics from Engineering and IT to Economics and Business.
- A site that brings both authors and readers into the world of free legal e-books. Authors with their e-books will benefit greatly from the large community of readers and the readers will in return, of course, will have lots of materials to read to their hearts’ content. Enjoy videos, infographics, lists and many more!
Internet Archive (https://archive.org/)
- It is a non-profit library of millions of free books, movies, software, music, websites, and more.
World Digital Library (https://www.wdl.org/en/)
- The World Digital Library is an international digital library operated by UNESCO and the United States Library of Congress.
- A source for manuscripts, rare books, films, maps and more in multilingual format.
Universal Digital Library (http://ulib.isri.cmu.edu/)
- A collection of one million books.
Google Books (https://books.google.com/)
- More than 100,000 books for consultation, download or on-line purchase.
Open Library (https://openlibrary.org/)
- More than one million e-books of classic literature to download.
- Open Library is an initiative of the Internet Archive, a 501(c)(3) non-profit, building a digital library of Internet sites and other cultural artifacts in digital form.
Galileo Open Learning Materials (https://oer.galileo.usg.edu/)
- GALILEO Open Learning Materials brings together open educational resources throughout the University System of Georgia, including open textbooks and ancillary materials.
- The MERLOT system provides access to curated online learning and support materials and content creation tools, led by an international community of educators, learners and researchers.
Million Book Project (https://archive.org/details/millionbooks)
eBooks Directory (https://www.e-booksdirectory.com/)
- It is a daily growing list of links to freely accessible e-books, documents and lecture notes found all over the internet.
- You can submit your own e-books, or add other resources you come across. Look below for the main directory of categories.
- Currently have exactly 10849 free e-books in 709 categories.
Free Book Spot (http://www.freebookspot.com)
- FreeBookSpot is an online source of free ebooks download with 4485 FREE E-BOOKS in 96 categories which up to 71,97 GB.
IntechOpen - (https://www.intechopen.com/books/subject/engineering - Covers Engineering | https://www.intechopen.com/books/subject/health-sciences - Covers Pharmacology, Toxicology & Pharmaceutical Sciences)
World’s largest Science, Technology & Medicine Open Access book publisher. The website contains more than 3,000 open access books distributed under CC BY 3.0 license in various subjects.
Free eBooks (https://www.free-ebooks.net/)
- Free-eBooks is an online source for free e-book downloads, e-book resources and e-book authors. Besides free e-books, you also download free magazines or submit your own e-book.