DEV.co
RAG Frameworks · shibing624

ChatPDF

ChatPDF is a Python-based RAG (Retrieval-Augmented Generation) system designed to run locally with open-source LLMs and embedding models, enabling question-answering over PDF, DOCX, Markdown, and TXT files. It supports GraphRAG, multiple LLM backends (Ollama, Deepseek, Qwen), and includes optimizations for Chinese and mixed-language document processing without requiring third-party agent libraries.

Source: GitHub — github.com/shibing624/ChatPDF
854
GitHub stars
144
Forks
Python
Primary language
Apache-2.0
License (OSI-approved)

Key facts

Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.

FieldValue
Repositoryshibing624/ChatPDF
Ownershibing624
Primary languagePython
LicenseApache-2.0 — OSI-approved
Stars854
Forks144
Open issues3
Latest release1.1.0 (2024-09-06)
Last updated2025-04-02
Sourcehttps://github.com/shibing624/ChatPDF

What ChatPDF is

Implements native RAG with local inference using pluggable embedding models, BM25 keyword matching, semantic similarity, optional reranking, and context expansion. Architecture supports async concurrent API requests, streaming responses via Gradio UI, and customizable LLM/embedding/reranker model selection through configuration parameters.

Quickstart

Get the ChatPDF source

Clone the repository and explore it locally.

terminalbash
git clone https://github.com/shibing624/ChatPDF.gitcd ChatPDF# follow the project's README for install & configuration

Need it deployed, integrated, or customized instead? DEV.co ships production installs.

Best use cases

Internal Document Q&A for Enterprise

Organizations seeking fully local, air-gapped document analysis without external API dependencies or data sovereignty concerns. Ideal for handling proprietary PDFs, compliance documents, or sensitive technical manuals on-premise.

Chinese/Multilingual Content Retrieval

Projects requiring robust handling of Chinese text mixed with English, leveraging jieba tokenization, optimized chunking strategies, and sentence-level embeddings tuned for cross-lingual semantic search.

Prototype RAG Systems with Minimal Dependencies

Teams prototyping RAG workflows who want to avoid heavyweight frameworks (LangChain, LlamaIndex) and prefer direct control over retrieval logic, embedding selection, and model inference.

Implementation considerations

  • GPU/CUDA availability required for acceptable inference latency; CPU-only deployments will be slow. NVIDIA GPU strongly recommended; test with target LLM model sizes before commitment.
  • Model selection is critical: memory footprint, inference speed, and RAG-specific tuning (e.g., 200k context models mentioned) vary significantly. Requires benchmarking with your document corpus.
  • Embedding model choice (local text2vec vs. HuggingFace vs. sentence-transformers) directly impacts retrieval quality; Chinese pipelines need validation on your language mix.
  • Dependency management: Python, CUDA toolkit version, and LLM framework versions (Ollama, transformers, torch) must be aligned; refer to requirements.txt and test in target OS (WSL recommended for Windows).
  • Reranker models and context expansion parameters require tuning per use case; default settings may not optimize for your document types or query patterns.

When to avoid it — and what to weigh

  • Need Managed Hosted Solution — If your team lacks GPU infrastructure, CUDA expertise, or DevOps capacity to deploy and maintain local LLMs. Managed services (OpenAI, Azure, Anthropic) require less operational overhead.
  • Require Enterprise Support & SLAs — This is a community-maintained project (854 stars, single primary maintainer contact listed). No commercial support, security bulletins, or guaranteed response times. Mission-critical workflows should use commercially backed alternatives.
  • Large-Scale Production at Latency Budget — Deploying across thousands of concurrent users with strict <500ms response SLAs. Local LLM inference is inherently resource-constrained; horizontal scaling requires significant engineering beyond the project scope.
  • Require Extensive Pre-built Integrations — If your stack depends on Slack, Salesforce, Jira, or other third-party connectors, this project requires custom integration work. No built-in connectors documented.

License & commercial use

Apache License 2.0 (Apache-2.0) is a permissive OSI-approved license allowing commercial use, modification, and distribution with minimal restrictions.

Apache 2.0 permits commercial deployment. README explicitly states "可免费用做商业用途" (free for commercial use) with requirement to include ChatPDF link and license in product attribution. No commercial support or warranty included; reliance on community support only. Review liability and indemnification carefully for mission-critical deployments.

DEV.co evaluation signals

Editorial assessment — not user reviews. Directional, with an explicit confidence level.

SignalAssessment
MaintenanceActive
DocumentationAdequate
License clarityClear
Deployment complexityModerate
DEV.co fitGood
Assessment confidenceHigh
Security considerations

Local-by-design reduces data exfiltration risk vs. cloud APIs, but introduces new concerns: (1) GPU server security and network isolation required if exposed to internet; (2) no mention of input sanitization for document parsing (PDF/DOCX attack surface); (3) API key management for optional OpenAI/Deepseek backends not discussed; (4) no authentication or audit logging in Gradio UI. For production, add WAF, input validation, secrets management, and access controls externally.

Alternatives to consider

LangChain + LlamaIndex + local LLMs

More mature ecosystems with extensive integrations, better documentation, and larger communities. Heavier dependencies but wider industry adoption and easier hiring.

Ollama alone + custom RAG logic

Simpler, lighter-weight alternative if you prefer to build retrieval yourself. Less opinionated; more control but higher engineering burden.

Managed RAG services (Azure AI Search, AWS Kendra, Pinecone + LLM APIs)

Outsource infrastructure, scaling, and security concerns. Higher cost but operational simplicity and enterprise SLAs; better for teams without ML DevOps expertise.

Software development agency

Build on ChatPDF with DEV.co software developers

ChatPDF is ideal for teams seeking sovereign, offline document Q&A. Assess GPU resources, model selection, and integration scope with our team before deployment.

Talk to DEV.co

Related open-source tools

Surfaced by semantic similarity across the DEV.co open-source index.

Related on DEV.co

Explore the category and the services that help you build with it.

ChatPDF FAQ

Can I use ChatPDF without a GPU?
Technically yes via CPU-only mode, but inference will be very slow (minutes per query). NVIDIA GPU with CUDA is strongly recommended. Memory: expect 8–24 GB depending on model size.
Does ChatPDF send my documents to external services?
No, by design. Local mode uses local LLMs and embeddings. Optional API backends (OpenAI, Deepseek) only if explicitly configured; you control which LLM endpoint is used.
How do I add support for non-English documents?
The project is optimized for Chinese + English via jieba tokenization and text2vec embeddings. For other languages, test with your embedding model and consider reranker tuning. Custom chunking logic may be needed.
What is GraphRAG and is it required?
GraphRAG builds a knowledge graph from documents for richer retrieval; it is optional. Standard flat RAG (keyword + semantic) is the default. GraphRAG demo requires OpenAI API key; see graphrag_demo.py.

Work with a software development agency

From first prototype to production, DEV.co delivers software development services around tools like ChatPDF. Our software development agency staffs experienced software developers and web developers for custom software development, web development, integrations, and ongoing support across rag frameworks and beyond.

Ready to Deploy Local RAG?

ChatPDF is ideal for teams seeking sovereign, offline document Q&A. Assess GPU resources, model selection, and integration scope with our team before deployment.