Tag
Pdf tools
4 reviewed tools: 4 free or open source.
Order: free and open source first, then hosted products with a real free tier, then paid-led; catalog order inside each group, with quiet or archived repos last. Not a score, and no tool pays for its place.
4 tools
- DoclingMIT local document parser that feeds PDFs and Office files into gen-AI pipelines
Free / OSS · OSS/MIT · 69.1k GitHub stars
VerdictMIT document AI for agent/RAG ingest. Default when PDFs and Office files must become structured context locally.
CatchVs MinerU and plain OCR pipelines: Docling is the broader multi-format DoclingDocument stack with gen-AI export paths — still expect GPU/CPU cost on heavy PDF batches and imperfect table recovery on ugly scans. Local models and extras increase install weight versus a thin Markdown converter.
- LiteParseApache-2.0 local PDF/doc parser — PDFium + OCR, no cloud required
Free / OSS · Apache-2.0 · 12.9k GitHub stars
VerdictApache local parse when agents need fast PDF→Markdown on-box — not LlamaParse cloud; escalate hard scans deliberately.
CatchVs LlamaIndex (framework) and cloud LlamaParse: LiteParse is the local OSS parser binary/bindings; LlamaParse cloud is the upsell for dense tables/scans/handwriting. Hard docs still want LlamaParse or another heavy parser — do not pretend local PDFium equals production OCR SaaS.
- PageIndexMIT self-hosted vectorless tree-RAG core — local mode with your own LLM key
Free / OSS · OSS/MIT · 39.3k GitHub stars
VerdictMIT self-hosted tree-RAG core for long text-heavy PDFs with your own LLM key — not the freemium pageindex-mcp; OCR, folders, metadata, MCP, and File System are cloud.
CatchCloud: OCR and image understanding, Metadata, Folders, the MCP server, and the PageIndex File System (corpus-scale indexing) are PageIndex Cloud only — need a PageIndex API key. Local mode is text-heavy PDFs, one document tree at a time. Not a duplicate of the pageindex-mcp gem: that one is the freemium hosted MCP surface; this is the self-hosted MIT tree-RAG core you run in your own code. Your LLM key pays for every index and query — tree reasoning is token-hungry on big docs. SDK is young (0.2.x); pin it.
- GotenbergMIT Docker API that turns HTML and Office files into PDFs
Free / OSS · OSS/MIT · 13.3k GitHub stars
VerdictThe default way to add HTML or Office-to-PDF to any backend — keep it on your private network.
CatchIt converts to PDF, not from it: it won't turn a PDF back into Word or text. It is a service you run next to your app, not a library you import, so you deploy, scale and secure the container yourself, and the bundled Chromium and LibreOffice make it a heavy image. Keep it off the public internet: its URL route fetches whatever address it is sent.
FAQ
- What is the top free pick among Pdf tools?
- Docling leads the Stack Gems list for Pdf tools. Verdict: MIT document AI for agent/RAG ingest. Default when PDFs and Office files must become structured context locally.
- How many Pdf tools does Stack Gems review?
- 4: 4 free or open source. Each review has a verdict and an honest Catch; no tool pays for its spot.
- Which Pdf tools can I self-host for free?
- Docling, LiteParse, PageIndex and Gotenberg.
- Which Pdf tools have the most GitHub stars?
- Docling (69.1k), PageIndex (39.3k), Gotenberg (13.3k), per GitHub on 2026-10-19. Stars measure attention, not fit; read the Catch.
- What is the catch with Docling?
- Vs MinerU and plain OCR pipelines: Docling is the broader multi-format DoclingDocument stack with gen-AI export paths — still expect GPU/CPU cost on heavy PDF batches and imperfect table recovery on ugly scans.