Open source alternatives to ChatPDF

By GitHub stars it is AnythingLLM, with 68,248 stars and a commit on 13 Nov. Choose AnythingLLM when your documents must stay on your own computer, with no daily document limit like ChatPDF's free plan. Next come Khoj (38,125 stars) and SurfSense (16,867 stars).

Yes. The code of all 3 is public under MIT, AGPL 3.0 or Apache 2.0, so you can use them with no licence fee. Running one yourself costs the server and your time to look after it, and some makers also sell a hosted plan.

Start from the job you use ChatPDF for. Choose Khoj when you want to question many PDFs, Markdown, Word and org-mode files at once, with the files kept on your machine. Choose SurfSense when you need cited answers across Word, Excel, slides and scanned PDFs on your own computer, plus edits as tracked changes.

All 3: AnythingLLM, Khoj and SurfSense. Each tool's page says what it needs to run.

2 of the 3 we track had a commit in the last 30 days, among them AnythingLLM and SurfSense. The quietest is Khoj, last changed on 2 Aug. A recent commit shows the project is kept up, not that it will stay that way.

MIT (1), AGPL 3.0 (1), Apache 2.0 (1). MIT, BSD and Apache let you change and reuse the code freely. GPL and AGPL ask you to share your changes under the same licence when you give the software to others, and AGPL also counts letting people use it over a network.

The hosting. ChatPDF's maker runs the servers for you; with an open source tool the updates, backups, security fixes and support are yours, unless you take the maker's hosted plan. Features differ too, so check what each one imports and exports before you move your data.