Yes — and the right approach depends on whether you want a visual side-by-side view or an automated comparison that highlights every difference between the two files. Both are useful, but they serve different purposes and require different tools.
Visual Side-by-Side: Two Windows, One Screen
The simplest approach: open both PDFs in separate windows and arrange them side by side on your screen. On Windows, open both in your PDF viewer, then use the Snap window feature (drag each window to opposite halves of the screen) to view them simultaneously. On Mac, use Split View (hold the green full-screen button and drag to a side) or simply resize and position two windows manually.
This works well for a quick visual check — scanning for obvious changes, comparing layouts, reviewing before-and-after versions of a design. The limitation is that you're doing the comparison manually: your eyes have to find the differences rather than software highlighting them for you.
Automated Comparison: Finding Every Difference
For contracts, legal documents, financial reports, or any situation where missing a single changed word has real consequences, automated comparison is the right tool. PDF comparison software analyzes both documents and highlights additions, deletions, and changes — similar to Track Changes in Word, but applied to two PDF files.
Adobe Acrobat Pro has a built-in compare feature (Tools → Compare Files) that produces a detailed difference report showing every change between two PDFs. It handles both text changes and visual differences, and can work on scanned documents by running OCR first.
Free Alternatives for PDF Comparison
Several free and lower-cost options handle PDF comparison for common use cases. DiffPDF is a free desktop application that compares PDFs page by page and highlights differences visually. PDF24 and similar browser-based tools offer basic comparison features. For text-focused documents, converting both PDFs to Word and using Word's built-in Track Changes comparison (Review → Compare) is often the most accessible free approach.
The conversion-to-Word approach works well for documents that are primarily text. For PDFs with complex layouts, forms, or precise formatting where position matters as much as content, a dedicated PDF comparison tool produces more reliable results.
Comparing Scanned PDFs
Comparing two scanned PDFs is harder than comparing digitally created ones because the comparison software has to work with images rather than text. Two approaches: run OCR on both files first to add text layers, then compare the text layers; or use image-based comparison that highlights visual differences pixel by pixel.
OCR-then-compare is more accurate for finding text changes but may miss visual differences like stamps, handwritten annotations, or formatting changes that OCR doesn't capture. Image-based comparison catches everything visible but can produce a lot of noise from slight misalignments, scanner variations, or JPEG compression differences between the two scans.
When to Use Each Approach
Manual side-by-side: quick visual review, layout comparison, design review, or when you need context around any differences rather than just a list of what changed. Automated comparison: contract review, regulatory document verification, any situation where completeness of the comparison matters and manual review might miss something. For high-stakes document comparison — legal agreements, regulatory filings, financial statements — automated comparison isn't optional; the risk of a missed change is too high to rely on human attention alone.