🧩 AI FrameworksOpen SourceFree

Unstructured

Document preprocessing — any format to LLM-ready chunks

4.3/ 5⭐ 12,000 GitHub starsPythonApache-2.0

⭐ Star on GitHub ☁️ Try Unstructured Cloud Free 🚀 Deploy on PyPI

📋 Overview

Unstructured provides document preprocessing that converts any file format (PDF, Word, Excel, HTML, images) into LLM-ready chunks. Unlike Marker (which focuses on PDFs), Unstructured handles 20+ file formats with a unified API. It provides a comprehensive solution for modern AI workflows. The library provides pre-built connectors for popular data sources including databases, cloud storage, and SaaS applications. It handles complex document layouts, tables, and embedded images with high accuracy. The output is structured and ready for LLM ingestion, making it ideal for RAG pipelines and knowledge base construction.

✨ Key Features

•12K+ GitHub stars — multi-format document preprocessing
•20+ file formats supported
•OCR for images and scanned documents
•Table extraction and preservation
•Open-source library and cloud API
•Apache 2.0 licensed
•Unified API
•Cloud option

🎯 The Problem It Solves

RAG pipelines need to ingest documents in many formats — each requiring different parsing logic. Unstructured provides a unified API for all formats.

🔧 How It Works

Unstructured detects file type, applies appropriate parsing (OCR for images, table extraction for PDFs, structure detection for HTML), and outputs clean chunks with metadata.

🚀 Installation & Quick Start

Installation

See website

Quick Start

See documentation

✅ Pros

•Most versatile document preprocessing
•20+ file formats
•OCR built-in
•Apache 2.0 licensed
•Unified API
•Cloud option

❌ Cons

•Open-source library requires setup
•Cloud API costs add up
•Complex documents need review
•Setup required

💬 Practitioner Verdict

“Unstructured is the most versatile document preprocessing tool — the multi-format support is genuinely differentiated. The trade-off: the open-source library requires significant setup, the cloud API costs add up, and complex documents still need review.”