The demo document is not your document
Every comparison tool looks good on a two-page sample. The differences show up on a forty-page contract with running headers, a specification with tables, or a scanned agreement with an OCR layer. Test on your own documents, and test on a pair where you know exactly what changed.
Six things to check
- Content alignment. Insert one sentence on page two and confirm the tool reports one change, not every later page.
- Headers and footers. Confirm that page numbers and repeated headers are not reported on every page, and that a changed footer is reported once.
- Tables. Confirm that an unchanged table produces no changes, and that a changed cell is reported as that cell.
- Moves. Move a paragraph and confirm it is reported as a move, not as a deletion plus an insertion.
- Formatting. Confirm that bold or font changes are classified separately from text changes and can be hidden.
- Determinism. Run the same pair twice and confirm the result is identical. A tool that uses a language model to decide what changed may not pass this.
Desktop, web or API
Desktop tools keep documents on the machine but tie the comparison to one user and one operating system, and are priced per seat. Web tools are available to everyone immediately, and the good ones process documents in memory without storing them. An API is what you need when the comparison should happen inside another system. Prefer a vendor that offers the web tool and the API on the same engine, so results match, and that can deploy privately for documents that cannot leave your network.
Try it
The comparison tool on this site is free for documents up to 30 pages with no account. Run the six checks above on your own documents and see what the change list looks like.
Try it on your own documents. Upload two versions on the homepage. Documents up to 30 pages need no account, and nothing is stored.