About SimpleFileTools

SimpleFileTools is a PDF comparison service for teams that need to know exactly what changed between two versions of a document, and to prove it.

Where the engine comes from

The comparison engine was built for pharmaceutical label surveillance: comparing revisions of FDA prescribing information and reporting every changed warning, dose and contraindication, without missing one and without drowning reviewers in false positives from reflowed text or repeated footers. That is a demanding benchmark. The same engine now runs behind this site and the API.

How it is different

• Content-aligned, not page-aligned. Paragraphs are matched across the two documents before comparing, so an inserted sentence is one change, not a shifted page.
• Layout aware. Running headers and footers, page numbers, unchanged tables and two-column layouts are all handled rather than reported as noise.
• Deterministic. The diff is rules-based. No language model decides what changed, so the result is reproducible and can be validated.
• Built for integration. One API call returns the change list as JSON, the redlined PDF and the side-by-side view.

Data handling

Documents are processed in memory and discarded when the response is sent. Nothing is written to permanent storage. Enterprise customers who cannot send documents outside their network can run the engine privately.

Contact

Email contact@simplefiletools.com or use the contact page to book a demo or request API access.