Free textbooks are easy to find and easy to get wrong. The search that turns up OpenStax also turns up sites whose operators have been indicted, and the download button looks the same on both. EdCitation publishes this guide to the sources that are legal, what each holds, how each is licensed, and how to cite a book from any of them, which EdCitation's free Cite a source does from the book's ISBN or DOI.
Every fact about another site was read on its own pages, checked on 23 September 2026, with counts as the pages showed them.
Which sites offer free textbooks legally?
Eight sources are legal to read free: three open textbook publishers or catalogues, a directory of open access books, two university presses, the public domain, and your own library.
| Source | What it holds | Licence or status | Cost | Cite it by |
|---|---|---|---|---|
| OpenStax | Peer-reviewed college textbooks | CC BY-NC-SA | Free; print at low cost | ISBN or URL |
| Open Textbook Library | 1,882 open textbooks, about 70% reviewed | GNU or Creative Commons | Free | ISBN or URL |
| LibreTexts | 17 subject libraries | Open licence shown on each text | Free | URL and the date read |
| DOAB | Over 109,000 peer-reviewed open access books | Open access, screened publishers | Free | DOI or ISBN |
| MIT Press Direct to Open | About 60 new monographs a year | Open access paid for by libraries | Free online | DOI or ISBN |
| Cambridge open access books | 706 books, 385 Elements | CC BY-NC-ND by default | Free online | DOI |
| Project Gutenberg | 75,000+ ebooks out of US copyright | Public domain in the US | Free | Original year and URL |
| Libby (OverDrive) | Your library's licensed ebooks | Borrowed for a loan period | Free with a library card | The book, never the app |
| EdCitation Library | One catalogue of textbooks and scholarly books across disciplines; with Max, read or borrow from more than 5 million books | Part of the Max plan | $24 a month | ISBN or DOI |
The first eight rows are the free sources. The ninth is EdCitation's own catalogue, which puts textbooks and scholarly books in a single search. Where the last column names an ISBN, a DOI or a URL, that is what to paste into Cite a source when the time comes to reference the book.
What does OpenStax publish, and how is it licensed?
OpenStax publishes peer-reviewed college textbooks that are free to read online or download as a PDF, and Rice University runs it as a nonprofit; print copies are sold at low cost (OpenStax, n.d.-a). Its FAQ says all OpenStax content is under the Creative Commons Attribution-NonCommercial-ShareAlike licence, with a pre-formatted attribution at the foot of every page of the online view (OpenStax, n.d.-b).
The Biology 2e page, for example, lists three senior contributing authors, a publish date of 28 March 2018, an ISBN-13 for the digital PDF (978-1-947172-52-4) and a licence line naming CC BY-NC-SA 4.0 (Clark et al., 2018).
What is in the Open Textbook Library and LibreTexts?
The Open Textbook Library is a catalogue of complete open textbooks with faculty reviews; LibreTexts is a platform where open texts are built and read.
The Open Textbook Library
Its home page showed 1,882 open textbooks on 23 September 2026 (Open Textbook Library, n.d.-c), and it is run by the Open Education Network at the University of Minnesota's Center for Open Education (Open Textbook Library, n.d.-b).
A book must be openly licensed under a GNU or Creative Commons licence without the No Derivatives condition, complete in a portable file such as PDF or EPUB, in use at more than one higher education institution or affiliated with one, and original rather than a derivative of another textbook (Open Textbook Library, n.d.-a). Reviews come from faculty at Open Education Network member institutions, and around 70% of the books have one (Open Textbook Library, n.d.-b). A review is one teacher's opinion: read it, then read the book.
LibreTexts
LibreTexts calls itself a non-profit platform of 17 subject libraries; its founder is Delmar Larsen, a chemistry professor (LibreTexts, n.d.-b). Its pages disagree on size: the home page says 3,000+ textbooks, the about page over 2,000 textbooks and 4,000+ published OER books (LibreTexts, n.d.-a, n.d.-b). Neither names one licence for the whole collection: take it from the text itself, and record the date you read it, since a page has no fixed edition.
Where do I find free academic books, not only textbooks?
Search DOAB, then the university presses that publish open access monographs, which are the studies a paper cites for their findings.
DOAB, the Directory of Open Access Books
DOAB describes itself as a community-driven discovery service for scholarly, peer-reviewed open access books; its home page counted over 109,000, and its services are free (DOAB, n.d.-a). The OAPEN Foundation established it in 2012; it is now run by the DOAB Foundation, a Dutch non-profit set up in 2019 by OAPEN and OpenEdition, and it lists publishers of academic, peer-reviewed open access books (DOAB, n.d.-b).
University presses
MIT Press Direct to Open opens about 60 new monographs and edited collections a year, paid for by participation fees from libraries rather than by readers or authors; the page calls this diamond open access, print copies are sold, and the backlist is counted as about 2,400 titles in one place and 2,500 in another (MIT Press, n.d.).
Cambridge University Press listed 706 open access books and 385 open access Elements on its open access page (Cambridge University Press, n.d.-a). Its gold open access books carry CC BY-NC-ND unless a funder asks otherwise, are paid for by a book processing charge of £10,500 for a monograph of up to 120,000 words, and are read on Cambridge Core (Cambridge University Press, n.d.-b).
What is Project Gutenberg, and what does public domain mean?
Project Gutenberg is an online library of more than 75,000 free ebooks that are out of copyright in the United States (Project Gutenberg, n.d.-a). The public domain, in the words of Duke Law School's Center for the Study of the Public Domain (n.d.), is material "unprotected by intellectual property rights and free for all to use or build upon".
Project Gutenberg checks each book against United States rules only, under which the longest US term for an older published work is 95 years from first publication, and where a book is distributed in another country that country's law applies (Project Gutenberg, n.d.-b). A classic novel or a century-old treatise is here; this year's chemistry textbook is not.
Cite a Gutenberg book as a republished book: the edition's year first, "Original work published" and the original year at the end, and both years with a slash in the text (American Psychological Association, 2020).
Can I borrow ebooks free from my library?
Yes. Libby, built by OverDrive, lets you borrow ebooks, audiobooks and magazines free from your local library; you need a card from a participating library, and the titles are the ones your library chose (OverDrive, n.d.).
A borrowed ebook is cited as the book, not the app: APA leaves the format, platform or device out of the reference (American Psychological Association, 2020).
What about the Internet Archive, Z-Library and Library Genesis?
The Internet Archive's lending of scanned books still in copyright was held not to be fair use, and Z-Library and Library Genesis are not legal sources.
Four publishers sued the Internet Archive in 2020 over 127 books; the district court found infringement, and on 4 September 2024 the Second Circuit affirmed. Hachette Book Group, Inc. v. Internet Archive (2024) asked whether a nonprofit may scan whole print books and lend the digital copies online, in full and free, one digital copy for each print copy owned, without permission, and answered no: the use was non-commercial but not transformative, all four fair use factors favoured the publishers, and the injunction covering the publishers' print books available for electronic licensing stood. A public domain scan is untouched by the ruling.
Z-Library and Library Genesis are pirate sites. On 16 November 2022 the U.S. Department of Justice (2022) announced an indictment charging two Russian nationals with criminal copyright infringement, wire fraud and money laundering for operating Z-Library, which the release says claims more than 11 million ebooks, and about 249 of its domains were seized under a court order. The indictment runs to five counts (United States v. Napolsky, 2022); the charges are allegations and the defendants are presumed innocent. For Library Genesis, Reid (2017) reported in Publishers Weekly that a federal court in New York awarded Elsevier $15 million in damages against Sci-Hub and Library Genesis in June 2017; the court's own records could not be read for this guide, because the case-law sites holding them refused automated reading.
How much do textbooks cost?
About 2.6 times what they cost in 2001, by the one official index. The U.S. Bureau of Labor Statistics (n.d.) prices college textbooks as a Consumer Price Index item, defined as a book a college, department or professor designates as required, new copies only. The index is set at 100 for December 2001; the U.S. Bureau of Labor Statistics (2026a) reported 259.660 for August 2026, 1.1% lower than in August 2025 (U.S. Bureau of Labor Statistics, 2026b).
Florida Virtual Campus (2022) surveyed 13,831 students at 30 public colleges and universities between 14 March and 13 May 2022: 53.5% had not bought a required textbook because of its cost, 43.7% had taken fewer courses, 38.5% had not registered for a course, 32.4% said they had earned a poor grade because they could not afford the book, and 24.2% had dropped a course; 44.4% had been given at least one open educational resource.
How do I cite a free textbook?
Start from the ISBN or the DOI, give the edition, and ignore the licence. A free book is referenced exactly like a paid one.
ISBN or DOI first
The record behind an ISBN or a DOI carries the authors, year, edition and publisher as the publisher registered them. APA's rules for a book are short: a DOI, if there is one, goes after the publisher; an ebook without a DOI takes its stable URL; a database or platform is never named; the edition goes in parentheses after the title; and the year is the copyright page's (American Psychological Association, 2020). If DOIs are new to you, read what a DOI is. The licence changes what you may do with a book, not how you cite it.
A worked example
From the Biology 2e page, in APA 7:
Clark, M. A., Douglas, M., & Choi, J. (2018). Biology 2e. OpenStax. https://openstax.org/details/books/biology-2e
In the text: (Clark et al., 2018). The authors are the senior contributing authors the page names, the year its publish date, and the edition sits in the title as OpenStax gives it; check the PDF's copyright page before handing in.
The same reference, built with EdCitation
- Copy the ISBN from the book's page. For Biology 2e, the digital PDF's is 978-1-947172-52-4.
- Paste it into EdCitation's Cite a source and pick your style from the six it offers. There is no charge and no sign-up.
- The ISBN is matched in Open Library, and the author names are taken from the record for that exact edition. Hold them against the names on the book's page: an open textbook can credit contributors beyond its senior authors, and the reference names the people the book presents as its authors.
- Check the title. In APA 7 and Vancouver, Cite a source sets it in sentence case, as those styles ask, and keeps names and initialisms; glance at any name made of ordinary words.
Which style you need is in APA, MLA or Chicago.
Is there one place to find the books and cite them?
Yes: EdCitation's Library, and it is the best tool for a student who wants the books and the citation in one place, because this guide has just walked through eight separate sites, each with its own search box, its own licence terms and its own way of recording a book, and the Library puts textbooks and scholarly books in one catalogue searched by discipline, kind, language and year. It lets you buy the paid titles, see which libraries near you hold a book, and keep all of them together in My Books; with Max, you can read or borrow from more than 5 million books.
Why the citation half matters
The reference is where a chatbot fails and EdCitation does not. A chatbot asked to cite a textbook writes the entry, and it has no way to look the edition up; Cite a source takes the ISBN or DOI and builds the entry from the record, and EdCitation never writes a reference. The worked example above shows why that matters for a free book: the ISBN on the OpenStax page belongs to one format of one edition, and a reference built from it describes that edition rather than a guess at it.
What each part costs
Three tools are free on the site and need no account: Cite a source, Find sources and Verify references. The Library comes with Max ($24 a month, or $216 for a year), along with Theoretics QA. Pro ($8 a month) is the plan for Check AI, Check plagiarism, Mechanics QA and References from a file. Both plans are on Pricing.
Quick questions
Is OpenStax really free?
Yes. OpenStax says every textbook in its library is free to read online or download as a PDF, with print copies sold at low cost, under a Creative Commons Attribution-NonCommercial-ShareAlike licence.
Is Z-Library legal?
No. In November 2022 U.S. prosecutors in Brooklyn charged its two alleged operators with criminal copyright infringement, wire fraud and money laundering, and about 249 of its domains were seized under a court order; the charges are allegations and the defendants are presumed innocent.
Can I use a Project Gutenberg book in an assignment?
Yes, if an old edition suits the task: Project Gutenberg's more than 75,000 ebooks are out of copyright in the United States. Cite the edition you read with its original year, and check that your own country's law also puts the work in the public domain.
Is the Internet Archive legal to read from?
Its public domain scans are unaffected by the 2024 ruling. Its lending of scanned books still in copyright was held not to be fair use by the Second Circuit on 4 September 2024.
What is the quickest way to cite a free textbook?
Paste its ISBN or DOI into EdCitation's free Cite a source and choose your style; the licence plays no part in the reference. Compare the authors with the book's own page; in APA 7 and Vancouver it sets the title in sentence case for you.
References
- American Psychological Association. (2020). Book/ebook references. APA Style. https://apastyle.apa.org/style-grammar-guidelines/references/examples/book-references
- Cambridge University Press. (n.d.-a). Open access. Retrieved 23 September 2026, from https://www.cambridge.org/core/publications/open-access
- Cambridge University Press. (n.d.-b). Gold open access books. Retrieved 23 September 2026, from https://www.cambridge.org/core/services/open-research/gold-open-access-books
- Center for the Study of the Public Domain. (n.d.). Public Domain Day: Frequently asked questions. Duke Law School. Retrieved September 27, 2026, from https://cspd.law.duke.edu/publicdomainday/faqs/
- Clark, M. A., Douglas, M., & Choi, J. (2018). Biology 2e. OpenStax. https://openstax.org/details/books/biology-2e
- DOAB. (n.d.-a). Directory of Open Access Books [Home page]. DOAB Foundation. Retrieved 23 September 2026, from https://www.doabooks.org/
- DOAB. (n.d.-b). About us. DOAB Foundation. Retrieved 23 September 2026, from https://doabooks.org/en/doab/purpose-of-doab
- Florida Virtual Campus. (2022). 2022 student textbook and instructional materials survey: Results and findings. https://www.flbog.edu/wp-content/uploads/2023/03/Textbook-Survey-Report.pdf
- Hachette Book Group, Inc. v. Internet Archive, No. 23-1260 (2d Cir. 2024). https://caselaw.findlaw.com/court/us-2nd-circuit/116548035.html
- LibreTexts. (n.d.-a). LibreTexts [Home page]. Retrieved 23 September 2026, from https://libretexts.org/
- LibreTexts. (n.d.-b). About us. Retrieved 23 September 2026, from https://libretexts.org/about-us
- MIT Press. (n.d.). Direct to Open. https://direct.mit.edu/books/pages/direct-to-open
- OpenStax. (n.d.-a). About us. Rice University. Retrieved 23 September 2026, from https://openstax.org/about
- OpenStax. (n.d.-b). FAQ. Rice University. Retrieved 23 September 2026, from https://openstax.org/faq
- Open Textbook Library. (n.d.-a). Open textbook criteria. Open Education Network. Retrieved 23 September 2026, from https://open.umn.edu/opentextbooks/books
- Open Textbook Library. (n.d.-b). FAQ. Open Education Network. Retrieved 23 September 2026, from https://open.umn.edu/opentextbooks/faq
- Open Textbook Library. (n.d.-c). Open Textbook Library [Home page]. Open Education Network. Retrieved 23 September 2026, from https://open.umn.edu/opentextbooks/
- OverDrive. (n.d.). Libby. https://www.overdrive.com/apps/libby
- Project Gutenberg. (n.d.-a). About Project Gutenberg. Retrieved 23 September 2026, from https://www.gutenberg.org/about/
- Project Gutenberg. (n.d.-b). Copyright how-to. Retrieved 23 September 2026, from https://www.gutenberg.org/help/copyright.html
- Reid, C. (2017, June 23). Elsevier awarded $15M in lawsuit against pirate sites. Publishers Weekly. https://www.publishersweekly.com/pw/by-topic/digital/content-and-e-books/article/74058-elsevier-awarded-15m-in-lawsuit-against-pirate-sites.html
- United States v. Napolsky, No. 22-CR-525 (E.D.N.Y. Nov. 16, 2022) (indictment). https://www.justice.gov/d9/press-releases/attachments/2022/11/16/z_library_indictment_0.pdf
- U.S. Bureau of Labor Statistics. (n.d.). College textbooks regression model. https://www.bls.gov/cpi/quality-adjustment/textbooks.htm
- U.S. Bureau of Labor Statistics. (2026a). Consumer Price Index for All Urban Consumers: College textbooks, U.S. city average (Series CUUR0000SSEA011) [Data set]. https://api.bls.gov/publicAPI/v2/timeseries/data/CUUR0000SSEA011
- U.S. Bureau of Labor Statistics. (2026b). Table 2. Consumer Price Index for All Urban Consumers (CPI-U): U.S. city average, by detailed expenditure category. https://www.bls.gov/news.release/cpi.t02.htm
- U.S. Department of Justice. (2022, November 16). Two Russian nationals charged with running massive e-book piracy website [Press release]. U.S. Attorney's Office, Eastern District of New York. https://www.justice.gov/usao-edny/pr/two-russian-nationals-charged-running-massive-e-book-piracy-website