PDF tools
Compare PDF
Text and metadata comparison report for two PDFs.
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Comparing two versions of a PDF document highlights exactly what changed between them — added text, deleted text, moved images, changed numbers. This is essential in legal, financial, and technical workflows where knowing the precise differences between a draft and a revised version is critical.
The comparison engine aligns the pages of two documents and performs text-level diffing, marking added content in green and removed content in red (or with standard redline notation). Changed sections are clearly flagged in the output report so reviewers can jump directly to modified areas without reading the entire document.
Lawyers use PDF comparison to check that contract revisions match what was negotiated. Auditors use it to compare financial statement drafts. Procurement teams use it to check that the final signed version of a tender matches the approved draft. Regulatory submission specialists use it to confirm that amendments to filed documents are limited to the approved changes.
How to use this utility
- Use the controls below—paste text, pick files, or adjust options as described on the tool.
- Click the main action button. Processing runs in your browser on this device.
- Download or copy the output. Check the processing note for any external services used by this operation.
Common use cases
- Comparing a vendor contract draft with the final signed version to detect unauthorised changes.
- Reviewing the differences between a financial statement draft and the auditor-approved version.
- Checking that a regulatory submission was amended only where approved.
- Verifying that an academic paper or thesis was not altered after the supervisor's approval.
- Comparing two versions of a policy document to identify and log all revisions.
Tips for best results
- 1Use the same page size and font settings in both PDFs for best comparison accuracy — mismatched pagination can shift line alignments.
- 2For scanned PDFs, run OCR on both files before comparing — text diffing requires a text layer.
- 3Large documents can produce long comparison reports — use the 'jump to change' navigation to review only modified sections.
- 4Save the comparison report PDF alongside both source documents for an auditable record of the change history.
- 5For legal documents, review the comparison output in detail rather than relying solely on the automated summary — some formatting differences can mask semantic changes.
Frequently asked questions
- Is Konnect2Tools free?
- Yes. These in-browser tools are completely free to use with no account required for core functionality.
- Do my files leave my device?
- Browser document operations run locally, except where the operation uses an external service, such as AI summarisation. Read the processing note before using sensitive inputs.
- Is the Compare PDF tool safe to use?
- Local operations process document content on your device. External-service operations may send inputs as described in the processing note. Keep originals and inspect the output.
- Can I compare PDFs that have different page counts?
- Yes — the tool aligns pages as best it can, and pages present in one document but not the other are flagged as entirely added or entirely removed.
- Does comparison work on scanned PDFs?
- Scanned PDFs require OCR to generate a text layer before text-based comparison is possible. Run the OCR PDF tool on both documents before comparing.
- How does the tool handle formatting changes (font, bold, italic) vs content changes?
- The tool highlights text content changes. Pure formatting changes (bold, italic, font size) may or may not be detected depending on how they affect the extracted text stream. For format-sensitive comparison, use a native PDF comparison tool like Adobe Acrobat.
- Can I compare password-protected PDFs?
- Remove passwords from both PDFs using the Remove PDF Password tool before comparing.
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