PDF Internals
Understanding PDF File Structure: A Deep Dive
Learn how PDF files are structured internally, from the header and body to the cross-reference table and trailer.
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Everything you need to work with PDFs — fast, free, and secure
Merge PDF Files
Combine multiple PDF files into one document. Drag and drop to reorder pages easily.
Compress PDF
Reduce PDF file size by up to 70% while maintaining quality. Perfect for email attachments.
Split PDF
Split a PDF into multiple files. Extract specific pages or split by page ranges.
E-Sign
Sign your PDF documents electronically with draw, type, or upload signature options.
Images to PDF
Convert JPG, PNG, and other image formats to PDF. Batch convert multiple images at once.
PDF to JPG
Convert PDF pages to high-quality JPG images. Export all pages or select specific ones.
Rotate PDF
Rotate PDF pages by 90, 180, or 270 degrees. Fix scanned documents and photos.
Add Watermark
Add text or image watermarks to protect your documents. Customize position and opacity.
Organize Pages
Rearrange, delete, or reorder pages. Full control over your PDF structure.
Page Numbers
Add page numbers to your PDF. Choose position, format, and starting number.
Crop & Resize
Crop margins, resize pages to standard sizes (A4, Letter), or set custom dimensions.
Technical Blog
Deep dives into PDF technology, web development, and best practices
Web Development
Client-Side PDF Processing with JavaScript
Explore how modern browsers can manipulate PDF files entirely on the client side using pdf-lib and PDF.js.
Optimization
PDF Compression Techniques Explained
Understand how PDF compression works, from object streams to image optimization and font subsetting.