The Free Adobe Acrobat Alternative

10M+ Downloads
Open Source
Privacy First
Self-Hosted

What is Stirling PDF?

Stirling PDF is a robust, web-based PDF manipulation tool. It enables you to carry out various operations on PDF files, including splitting, merging, converting, rearranging, adding images, rotating, compressing, and more.

50+ PDF Operations

Comprehensive toolkit covering all your PDF needs. From basic operations to advanced processing.

Workflow Automation

Chain multiple operations together and save them as reusable workflows. Perfect for recurring tasks.

Multi-Language Support

Available in over 30 languages with community-contributed translations. Accessible to users worldwide.

Privacy First

Self-hosted solution means your data stays on your infrastructure. You have full control over your documents.

Open Source

Transparent, community-driven development. Inspect the code, contribute features, and adapt as needed.

API Access

RESTful API for integration with external tools and scripts. Automate PDF operations programmatically.

Key Features

Page Operations

  • Merge & split PDFs
  • Rearrange pages
  • Rotate & crop
  • Extract pages
  • Multi-page layout

Security & Signing

  • Password protection
  • Digital signatures
  • Watermarks
  • Permission controls
  • Redaction tools

File Conversions

  • PDF to/from images
  • Office documents
  • HTML to PDF
  • Markdown to PDF
  • PDF to Word/Excel

Automation

  • Multi-step workflows
  • Chain PDF operations
  • Save recurring tasks
  • Batch file processing
  • API integration

Plus Many More

  • OCR text recognition
  • Compress PDFs
  • Add images & stamps
  • Detect blank pages
  • Extract images
  • Edit metadata
  • Flatten forms
  • PDF/A conversion
  • Add page numbers
  • Remove pages
  • Repair PDFs
  • And 40+ more tools