Compare PDF Files Online
Upload the original and revised versions of any PDF or Word document. Setpdf highlights every addition, deletion, and modification side by side — no manual review, no missed changes. Trusted by lawyers, editors, and engineers for fast, accurate document comparison.
Drag & drop or click to select
PDF / DOC / DOCX · 100 MBDrag & drop or click to select
PDF / DOC / DOCX · 100 MBHow to Compare PDF Files Online
Compare two versions of any document in seconds — no software installation required.
Upload the Original Document
Click or drag your original PDF, DOC, or DOCX file into the left upload zone. This is the “before” version.
Upload the Modified Document
Drop the revised version into the right upload zone. Supports PDF and Word (.doc/.docx) formats, up to 100 MB per file.
Click “Start Comparison”
Hit the button and Setpdf instantly extracts text from both files and identifies every change — no manual work required.
Review Highlighted Differences
Additions are marked in green, deletions in red, and edits in amber. Use j / k or the sidebar to navigate between changes.
Export Your Comparison Report
Download an annotated PDF with all changes marked inline — ideal for sharing with colleagues or keeping as an official record.
Why Professionals Choose Setpdf Compare
Built for precision — not just matching lines, but understanding documents.
Compare Word (.docx / .doc) Against PDF
Most tools only compare PDF to PDF. Setpdf is one of the few that lets you upload a Word document on one side and a PDF on the other — perfect for reviewing contract revisions, checking export fidelity, or tracking draft-to-final changes without manual conversion.
100% Sync Scroll
Both documents scroll in perfect lockstep, keeping insertions and deletions aligned as you review long multi-page files.Blackline PDF Export
Download a redline PDF with additions and deletions marked inline — ready for legal sign-off, audit trails, or client delivery.CJK Precision (Chinese / Japanese / Korean)
Accurate character-level diffing for CJK scripts, where word boundaries are invisible — catching changes that byte-based tools miss entirely.Word-Level Diff Highlighting
Changes are highlighted at the word level, not just line-by-line, so you can pinpoint exact edits even in dense paragraphs.No Install, No Sign-Up Required
Start comparing immediately in your browser — no extension, no desktop app, and no account needed for basic use.Keyboard Navigation
Jump between changes instantly with j / k shortcuts — no mouse needed when reviewing dozens of edits across long documents.Frequently Asked Questions
Answers to the most common questions about comparing PDFs and Word documents online.
How accurately does Setpdf detect subtle changes like decimal points or punctuation?
Standard line-based diff tools can miss a change from ‘180.0’ to ‘18.00’ if the surrounding text looks similar. Setpdf applies word-level tokenisation combined with a dedicated numeric and currency guard: a shift from ‘$1,200.00’ to ‘$1,020.00’ is flagged as a precise substitution rather than a line rewrite. This matters critically in financial statements, engineering specifications, and legal clauses where a single digit changes the meaning entirely.
What is Blackline (redline) comparison, and how does Setpdf generate a Blackline PDF?
Blacklining — also called redlining or tracked-changes markup — is the professional standard for annotating document revisions: additions underlined, deletions struck through. After a comparison, click Export to download an annotated Blackline PDF where insertions are marked in green, deletions in red, and substitutions in amber. The result is ready for legal sign-off workflows, audit trails, or client delivery without any additional formatting work.
Does the comparison work accurately for Chinese, Japanese, or Korean (CJK) documents?
Yes. CJK scripts have no white-space word boundaries, which breaks most standard tokenisers. Setpdf uses character-level segmentation specifically for Chinese, Japanese, and Korean text, so a single modified character inside a dense Chinese legal clause is detected and highlighted — a precision level that byte-based comparison tools commonly miss. This makes it reliable for Chinese contracts, Japanese technical manuals, and Korean regulatory submissions.
Can I compare scanned PDFs or image-based PDFs?
Scanned PDFs contain image data rather than selectable text, so text extraction requires OCR (Optical Character Recognition). Setpdf's comparison engine works on text-layer PDFs and Word documents. If your PDF is scanned, we recommend running it through an OCR tool first to generate a searchable text layer, then uploading the result for comparison.