What is Paper Knife PDF and how does it work?

Paper Knife PDF is a free, premium, privacy-focused offline document toolkit that allows users to edit, merge, split, compress, and secure PDF files directly in their browser. All operations are processed locally on the client-side device, preventing files from being uploaded to remote servers.

What is the Paper Knife Android application?

Paper Knife is the native Android app package for the Paper Knife PDF utility suite, available via the Google Play Store. It features a touch-optimized document camera scanner, signature stamp overlay, biometric security folder lock, and offline image processing tools.

Is Paper Knife PDF safe for processing highly confidential files?

Yes, Paper Knife PDF is entirely safe. Because it runs locally inside the web browser sandbox using client-side HTML5 and WebAssembly, your documents never leave your computer, ensuring absolute privacy for financial, legal, and corporate documents.

Does Paper Knife include offline image converters and compressors?

Yes, Paper Knife includes private offline image converters (PNG, JPG, WebP, BMP), image compressors, dimensions resizers, EXIF metadata strippers, and solid color keying background removers that execute client-side.

Paper Knife PDF — Offline PDF & Image Tools

Premium Offline PDF Tools

Our secure offline PDF tools let you process documents completely inside your browser sandbox. Your data remains private and secure.

PDF Editing Tools

Edit PDF: Draw annotations, add shapes, stamp text, and insert signatures.
PDF Highlighter: Highlight text and draw shapes in PDF files.
Flatten PDF: Convert interactive PDF forms or annotations to flat content.
Crop PDF: Trim the margins of PDF pages visually.
Redact PDF: Permanently blackout sensitive information in your PDF.
Invert Colors: Invert the color scheme of your PDF pages for dark mode.
Add Image: Overlay image files onto PDF pages.
Add Page: Insert blank pages or duplicate pages inside a PDF.
Delete Pages: Remove unwanted pages from a PDF document.
Header & Footer: Add page numbers, titles, or dates to headers/footers.
Sanitize PDF: Clean sensitive hidden metadata and links from PDF files.
Rotate PDF: Rotate specific or all pages in a PDF document.
Rearrange PDF: Reorder, drag-and-drop, or remove pages within a PDF.
Page Numbers: Stamp sequential page numbering onto your document.
Watermark: Add text or image watermarks behind page content.
Metadata: Edit title, author, subject, keywords, and metadata fields.
Signature: Draw, upload, or type digital signatures onto PDF pages.
Grayscale: Convert all colorful PDF contents to black and white.
Repair PDF: Fix corrupt, broken, or unreadable PDF structures.
Create PDF: Generate new empty PDF documents from scratch.
Reverse PDF: Invert page order sequence of your document pages.
Add Margins: Insert custom blank page margins and padding to your PDF.
Document Scanner: Use camera to scan physical papers into clean PDF documents.
Bates Numbering: Add legal index Bates numbers to page headers/footers.

PDF Optimization Tools

Merge PDF: Combine multiple PDF files into a single document.
Split PDF: Separate a PDF file into individual pages or specific ranges.
Compress PDF: Reduce the file size of PDF documents without losing quality.
PDF Imposition: Layout pages in custom printer imposition templates.
N-Up PDF: Layout multiple page pages in grid format on a single sheet.

PDF Security Tools

Protect PDF: Encrypt PDF files with a secure password lock.
Unlock PDF: Decrypt and remove password security from protected PDFs.

PDF Audio Tools

Text to Speech: Listen to spoken voice reading of text inside PDF files.
PDF Voice Dictation: Dictate text using your voice and compile it directly into a PDF document.

PDF Conversion Tools

PDF to Image: Extract and export pages as high-quality JPG/PNG files.
Image to PDF: Convert standard images (PNG, JPG) into PDF documents.
Extract Images: Pull out and download all embedded images from inside a PDF.
PDF to Text: Extract readable text contents or run OCR scanned page text.

Premium Offline Image Tools

Process your photos and raster/vector graphics completely client-side. Protect your image privacy with offline metadata removal, resizing, and filters.

Image Compress & Resize

Image Compressor: Reduce image file size while maintaining quality.
Image Resize: Resize images to specific dimensions or percentage scales.
Bulk Image Resizer: Resize multiple images in batch and download as a ZIP archive.

Image Format Converter

Image Converter: Convert images between different formats (JPG, PNG, WebP, BMP).
SVG to PNG Converter: Convert vector SVG layouts to standard PNG or JPG raster formats offline.

Image Filters & Effects

Image Filters: Apply filters like B&W, Sepia, Soft, or adjust colors.

Image Edit & Decorate

Meme Generator: Create custom memes with text and styling entirely offline.
Image Cropper: Crop, rotate, and flip images visually to any aspect ratio.
Image Borders & Corners: Add borders, frames, and rounded corners to images.
Image Watermark: Overlay logo images or text watermarks on images.

Image Utilities

Color Palette Generator: Extract dominant color palettes from any photo client-side.
Color Picker from Image: Extract exact Hex/RGB color values.
Image to Base64: Encode and decode images to Base64 strings.
Image Info Inspector: View dimensions, resolution, format details, and aspect ratios.
Image EXIF Stripper: Remove camera models, GPS coordinates, and dates from photos.
Image Background Remover: Remove solid colored backgrounds from images client-side.