Compare Differences Between Two PDFs

Sometimes, when dealing with PDF documents, we don’t need or want extra features and all that other jazzy stuff. We just want to be able to compare two similar documents and see how one differs from the other. This would be a lot of work for a mere mortal as he/she would have to manually scan each line of text or image and figure out what has or hasn’t changed. As you already might have guessed, that’s not a lot of fun. Even if the user doesn’t actually mind performing the tedious task, there is still the problem of human errors. Unless you compare text documents day in and day out on a regular basis, it’s safe to say that you might miss a slight change or so. That might not be important for ]your average files but what about legal or coding documents where a slight change in word can have a huge impact? In these cases, it’s definitely wise to to have an automated method of checking to see whether the two different documents have any changes or not. For that, we can use a free utility called DiffPDF.

You can download DiffPDF from here.

DiffPDF is a self-executable so what does that mean folks? You got it! Simply pop it in your USB thumb drive and you’ll be able to open it on pretty much any Windows operating system without any pre-installation. Just double-click on the .exe file and you’ll be good to go. DiffPDF won’t win any fancy GUI awards but that shouldn’t matter here. We just want to be able to compare two PDF files easily and efficiently.

By default, DiffPDF will compare text only. If you want to compare picture differences between the two PDF files, select the “Appearance” option under the Comparison Mode dropdown box. For some reason you cannot compare both text and pictures at the same time. It’s either or. To load your two PDF files for comparison, simply hit the File #1 button and browse for your file. Do the same for your second PDF file with the File #2 button at the top. Once both have been selected, hit the Compare button under the Actions menu. That’s it! You’ll immediately see the differences, if any, between both files. Beats doing it by yourself doesn’t it?!

The DiffPDF website provides two example PDF files for you to play with. If you do not currently have two similar PDF files to compare, use the samples to see how DiffPDF works.

As you can see, the differences will be highlighted in a light shade of red/pink.

You are able to select different highlight colors and styles but from my testing, the colors were not strong enough even with a white background like the example above. The default seems to work best but you’ll definitely want to adjust it depending on how your PDF files are formatted. You can configure these settings by simply hitting the Options button under the Actions panel.

As you can see, DiffPDF can save you a lot of time from having to manually comparing between two PDF documents, especially if they are mostly comprised of text. Why waste precious time doing it manually? However, if the document you are comparing is highly sensitive and very important, I would recommend using DiffPDF as well as trying to manually catch any changes between the documents. Of course, I’m sure you already have that one figured out. I mean, you do realize software can make mistakes as well, right?