PaperKnife: Work with PDFs on Your Device

Overview

PaperKnife is a PDF utility for merging, splitting, compressing, signing, and otherwise editing documents in a web app or Android app. Processing happens on the device, so it is designed for people who want to avoid uploading sensitive files to an online service.

The web app can be installed as a PWA for offline use, and Android builds are available. Deep OCR is available in the full version; the Lite release omits its OCR engine.

Key Features

• Merge and split PDFs.
• Compress PDFs using quality presets.
• Protect and unlock PDFs with passwords.
• Convert PDF pages to JPG or PNG at 72–300 DPI.
• Draw, upload, and reuse signatures.
• Add watermarks and page numbers, and clean document metadata.
• Extract text with Deep OCR in the full version.

Use Cases

• Individuals handling personal or confidential paperwork who want to edit PDFs without uploading them.
• Android users who need common PDF operations while offline or away from a desktop.
• People combining, splitting, or compressing documents before sharing or storing them.
• Users who need to sign, watermark, or add page numbers to documents locally.
• Users who need OCR, provided they use the full version and have its engine available.

Project Facts

• Language: TypeScript
• License: AGPL-3.0
• Stars: 1.5k
• Forks: 102
• Topics: android, capacitor, f-droid, offline-first, open-source, pdf, pdf-manipulation, pdf-tools, privacy, react, security, typescript, zero-server
• Archived: false

Getting Started

For the web version, clone the repository, install dependencies, and start the development server:

git clone https://github.com/potatameister/PaperKnife.git
cd PaperKnife
npm ci
npm run dev

See the README for Android build requirements, OCR setup, and other details.

Alternatives

• ImageToolbox: ImageToolbox includes PDF tasks within a broader Android image and media utility suite, while PaperKnife focuses on offline PDF workflows across web and Android.

Considerations

• The project requires Node.js 22 or later to run the web version locally.
• Deep OCR requires optional engine files, which are not included in a fresh clone. The README documents npm run vendor:ocr for setup.
• Building an Android APK also requires JDK 21 and the Android SDK.
• The AGPL-3.0 license has obligations for modified versions, particularly when they are made available over a network. Review the license before incorporating PaperKnife into another project.