Comparing Two PDFs

Note: Acrobat 9 has an updated Document Comparison function which works differently than that of Acrobat 8 and prior. To see a short demo movie of how it works in Acrobat 9, click here.

The other side is strictly maintaining document control for the new agreement you are negotiating. Opposing counsel will only give you a PDF and now there are several revisions.

If you had the original word processing files, you could compare them using a tool like Deltaview or perhaps the built-in tools provided in your word processor program.

But… you only have PDFs.

You need to find out what has changed.

What to do?

Fortunately, Acrobat Professional can create a side-by-side comparison report and to help you spot any changes.

Deletions are indicated with red strikethrough text:

Additions have blue underlines:

Read on to learn how to easily compare two documents using Acrobat.

Document Comparison using Adobe Acrobat

Adobe Acrobat Professional 7 and 8 offer the ability to compare two PDFs.

To compare to PDFs:

  1. Locate the original or older version of the file and open it in Acrobat
  2. In Acrobat 7, choose Document—>Compare Documents
    In Acrobat 8, choose Advanced—>Compare Documents
  3. Click the Choose . . . button and locate a newer version to compare
  4. Enable the Textual Differences radio button
  5. Enable the Side by Side Report radio button

Acrobat will produce a new PDF which contains a summary cover page:

Text Comparison Summary

If you scroll down, Acrobat will display the older document on the left and the newer document on the right.

Other Comparison Considerations

Note that Acrobat creates a new, temporary document which represents the comparison. Don’t forget to save it if you will need it later.

Acrobat can also spot visual differences between documents. For example, it is possible to compare drawings. However, Acrobat will detect the subtlest change—even a single pixel.