Compare Two PDFs: Review Text and Visual Changes

What does the comparison cover?

Compare PDF examines an original and a revised PDF in the browser. It reports extracted-text changes and visual differences for paired pages, and it records coverage so you can see which pages used native text, OCR, visual comparison, or no comparable text.

A detected change is a review lead. It does not decide whether the revision is correct, legally meaningful, or intentionally approved.

Run the first comparison

1. Select the original and revised PDFs. Confirm the filenames and page counts before starting.
2. Choose Compare files and inspect the change list, page pairs, linked highlights, and coverage notes.
3. Open each change and compare the highlighted area with the surrounding page. Mark a change reviewed only after deciding what it means.
4. Export a PDF or text report when you need a review record. The report includes the comparison settings and coverage notes.

Refine expected noise carefully

Settings can ignore spacing differences, letter case, the predefined outer margins, or up to 100 custom regions. Visual sensitivity can focus on larger differences or include smaller ones. Each exclusion can hide a real change, so record why you used it.

Automatic page matching can be corrected by pinning an original page to a revised page. Other pages are then matched around those choices. This is useful when inserted or removed pages shift the sequence.

Compare scanned documents

Enable “Recognize text with OCR” for image-only pages and choose the document language. OCR handles up to 100 pages per comparison. Recognition runs in the browser, and recognized names and numbers still need checking. Visual comparison can reveal appearance changes even when extracted text is incomplete; text comparison can identify word-level changes that are difficult to spot visually.

Illustrative revision example

This scenario is illustrative; it is not an observed accuracy or speed result. Suppose a revised contract adds a paragraph on page 3 and changes a footer date on every page. First review the added paragraph. If the footer changes are expected, ignore only that measured footer region and rerun the comparison. Record the ignored region in the exported report, then inspect any remaining visual-only changes.

Finish with source checks

• Confirm that paired pages contain corresponding content.
• Check pages listed without comparable text and any OCR pages.
• Review typography, images, charts, signatures, annotations, and page geometry even when extracted text matches.
• Keep both source PDFs with the report. A report summarizes one run with chosen settings; it does not replace the documents.

If the revised file was made in PDF Logic, the text-editing guide, watermark guide, and redaction guide provide operation-specific checks.