StackToPDF Documentation

Complete guide to using StackToPDF, the professional document scanning and OCR tool.

Free Core + Pro Add-on

StackToPDF core features are free forever. The Receipt Intelligence Pro add-on is a one-time $29 purchase.

Quick Start

  1. Install StackToPDF - Download and run the installer
  2. Add Images - Drag and drop images or use "Add Files" button
  3. Arrange Order - Drag pages to reorder if needed
  4. Enhance (Optional) - Auto-enhance for scanned documents
  5. Export - Click "Create PDF" to generate your document

Core Features (Free)

Image to PDF Conversion

  • Multiple Formats - Supports JPG, PNG, TIFF, BMP, and WebP
  • Batch Processing - Convert hundreds of images at once
  • Page Ordering - Drag and drop to arrange pages
  • Preview - See exactly what your PDF will look like

Image Enhancement

  • Auto-Rotate - Detect and correct page orientation
  • Deskew - Straighten tilted scans automatically
  • Contrast Adjustment - Improve readability of faded documents
  • Background Removal - Clean up scanned paper backgrounds

OCR (Tesseract)

Extract text from images using industry-standard Tesseract OCR:

  • 100+ Languages - English, Spanish, French, German, Chinese, and more
  • Searchable PDFs - Create PDFs with selectable/searchable text
  • Text Export - Export extracted text to TXT or Word
  • Offline Processing - All OCR runs locally on your machine

OCR Tip

For best OCR results, ensure images are at least 300 DPI and text is clearly visible. Use the "Enhance" feature to improve contrast before running OCR.

Receipt Intelligence Pro ($29)

The Pro add-on unlocks advanced receipt and invoice processing:

Smart Data Extraction

  • • Automatically detect vendor name, date, and total
  • • Extract line items with quantities and prices
  • • Identify tax amounts and payment method
  • • Parse structured data from invoices

Expense Categorization

  • • Auto-categorize receipts (food, travel, office, etc.)
  • • Custom category rules
  • • Monthly spending summaries
  • • Export to CSV for accounting software

Batch Receipt Processing

  • • Process entire folders of receipts
  • • Automatic file naming (vendor_date_amount.pdf)
  • • Duplicate detection
  • • Summary report generation

Settings

Output Settings

  • PDF Quality - Low (smaller files) to High (best quality)
  • Page Size - Auto, Letter, A4, or custom dimensions
  • Compression - JPEG, PNG (lossless), or JPEG2000
  • DPI - Output resolution (150, 300, or original)

OCR Settings

  • Language - Primary language for text recognition
  • Engine Mode - Fast, Standard, or Best (accuracy)
  • Output Format - Searchable PDF, text layer, or text file
  • Confidence Threshold - Minimum accuracy to include text

Enhancement Settings

  • Auto-Enhance - Apply all enhancements automatically
  • Deskew Threshold - Sensitivity for tilt correction
  • Background Color - White, off-white, or preserve original
  • Edge Detection - Crop to document edges automatically

Troubleshooting

OCR Text is Incorrect

  • • Ensure correct language is selected
  • • Use "Enhance" to improve image quality first
  • • Check image resolution (300 DPI minimum recommended)
  • • Try "Best" OCR engine mode for difficult text

PDF File Too Large

  • • Reduce output quality in Settings
  • • Use JPEG compression instead of PNG
  • • Lower output DPI to 150
  • • Enable image optimization

Receipt Pro Not Extracting Data

  • • Ensure receipt image is clear and well-lit
  • • Run enhancement before extraction
  • • Check that receipt is not upside down
  • • Some handwritten receipts may not be supported

Images Not Loading

  • • Check file format is supported (JPG, PNG, TIFF, BMP, WebP)
  • • Ensure file is not corrupted
  • • Try opening file in another application first
  • • Check available disk space

Keyboard Shortcuts

Ctrl+OAdd files
Ctrl+SSave/Export PDF
Ctrl+EEnhance selected
Ctrl+TRun OCR
DeleteRemove selected page
Ctrl+ASelect all pages

Need Help?

Visit our support portal or check the FAQ.