How to Compare Two PDF Versions
Use visual differences as evidence for review, not as a substitute for judgment.
Normalize expectations
Pixel comparison detects changes in position and appearance. A font substitution or one-line reflow can make an entire page look different even when the wording is nearly identical.
Review systematically
Compare corresponding pages side by side, then inspect highlighted differences. Check insertions, deletions, numbers, dates, names, signatures, headers, footers, and page order.
Document the decision
Keep the two source files and record which version was approved. For contracts or regulated records, use a text-aware review and human sign-off in addition to visual comparison.