AFileFix Document Comparison vs SmarterDiff

AFileFix Document Comparison is a free web tool for comparing one pair of document versions. It identifies added, removed, and modified text in PDF or DOCX files, including mixed-format pairs, with a 25 MB limit per file. Results appear on screen, and a downloadable DOCX report provides analysis and plain-English explanations of each change and why it might matter. The tool is recommended for structured, text-heavy documents such as contracts, policies, proposals, terms of service, and manuals.

Both files are sent to Anthropic's Claude API for processing. AFileFix says it removes uploaded files from its server within minutes. Anthropic retains API data for up to 30 days for safety review, then deletes it, and does not use it to train AI models. The comparison covers text, not layout-only changes such as fonts, spacing, page breaks, or margins. Scanned and password-protected PDFs are unsupported, and the tool does not OCR scanned files. Documents over approximately 150 pages may be truncated. It does not provide three-way comparison, Word track changes, or legal redline output.

SmarterDiff is a free browser-based tool for comparing text, Word documents, PDFs, spreadsheets, folders, and images. Text comparisons can show line, word, or character differences, with options to ignore case and whitespace. Excel and CSV comparisons check cell values and formulas, while image comparisons use pixel differences with overlay, side-by-side, and slider views. It can compare finalized.docx text, but not Word tracked-change markup; scanned PDFs without embedded text cannot be compared as text. SmarterDiff says comparisons run in the browser and files or results are not sent to its servers or external services. Comparisons can work offline after the first page load while browser libraries remain cached. File size depends on available computer memory and browser limits. It is a manual, one-off tool without workflow automation or integrations. The Free plan costs nothing, is ad-supported, requires no account, and has no artificial limits. Google AdSense may set ad-targeting cookies.