Compare Files Online — Free & Private
Drop two files in any combination — PDF, Word, TXT, Markdown or source code — and see every difference highlighted word by word. Everything runs in your browser; nothing is ever uploaded.
No comparison yet. Paste or upload text in both fields below — results appear here automatically, and nothing is calculated until you do.
Compare your two texts
Original Text (A)0 words
Modified Text (B)0 words
Supported File Formats
PDF (.pdf)
Text-based PDFs are parsed with pdf.js page by page.
Word (.docx)
Microsoft Word documents are converted via mammoth.js.
Text & Code
TXT, MD, JSON, source code — loaded directly, no conversion.
Why Compare Files in the Browser?
Instant. No upload roundtrip — the diff appears as soon as the file is parsed.
Private. Sensitive contracts, NDAs and source code never leave your computer.
Free forever. No accounts, no quotas, no ads.
Related comparison tools
How SnapTextCompare works
Diff engine
Google's diff-match-patch (Apache 2.0), running in your browser. Character mode diffs raw characters; word and line modes encode tokens or lines first and diff those, then decode the result.
Similarity & importance
Similarity = 1 − Levenshtein / max(len). Importance weighs each change by category — money and dates score 90+, punctuation scores 3. Deterministic on any device.
Privacy
Files are read with the HTML5 File API and processed in your browser. No network request is ever made with your content — verifiable in the Network tab of your browser's DevTools.
PDF extraction uses pdf.js (Mozilla). Word extraction uses mammoth.js. UTF-8 with or without BOM is auto-detected; CRLF line endings are normalised to LF before diffing so cross-OS files don't appear entirely changed.
File Comparison FAQ
Common questions about comparing files online.