When you need to spot the differences between 2 versions of a PDF document, you won’t strain your eyes and check lines after lines to find out the differences, right? Use a PDF compare tool, whether online free or online subscription services, or offline downloadable software, we’ve assembled 5 best PDF compare tools for you, try these suggestions.

  1. The Best PDF Compare Tool
  2. How to Compare PDFs Online Free
  3. Open-Source PDF Compare Software for Mac & Windows to Download

The Best PDF Compare Tool

Let’s start with the most efficient method: using Adobe Acrobat to compare 2 PDF documents and highlight the differences.

The primary job of Acrobat is to edit PDF, lets users have a full control of PDF texts, images, form fields, pages, etc. But Acrobat can do any task relating to PDF, including PDF Compare, Create, Export, Scan & OCR, Fill & Sign, Protect & Stamp…, with its incredibly useful tools and options, you can get back a substantial amount of time every time you deal with a PDF.

When comparing PDF files in Acrobat, you can compare a specified page range and auto detect differences by comparing Text, Image, Header/Footer, Annotation, Formatting, even Backgrounds. Surely, you can compare PDF text only. Acrobat will give a report, showing total changes and highlighting all the differences in your PDFs, using Side-by-Side view mode. It can find all differences accurately, highlighting all the changes in both Old and New files, so you can check out what exactly are the changes.

How to compare 2 PDFs side by side in Adobe Acrobat?

  1. Get a free 7-day trial of Acrobat. The pricing starts from $14.99~$24.99/month with cancellation at anytime.
  2. Fire up Acrobat app on your Mac or Windows machine.
  3. Go to Tools>Share & Review>Compare Files.pdf compare acrobat 1
  4. Import the old and new PDF file by clicking on Select file.pdf compare acrobat 2
  5. Click on the cog settings icon to set up your Compare preferences.pdf compare acrobat 3
  6. Hit Compare button. You will get a report and can find the differences from highlights in the side-by-side PDF file view mode.pdf compare acrobat 4

How to Compare PDFs Online Free

If you are not going to buy or install a new PDF compare on your machine for now, online free PDF Compare tools from web browsers will ride to the rescue and at your convenience.

Of the various online free PDF Compare tools, we like Draftable, Diffchecker and PDFForge.


This platform is built to compare 2 different versions of a Word, PowerPoint or PDF file in side-by-side view. It spots differences basing on content and style. There is no cost and no sign up needed to use this tool.

Here is the drawback. If contents are removed from the New PDF, it won’t highlight the difference, it just highlights the difference in the Old file that with original content kept.

Compare two PDF files side by side online free with Draftable

  1. Navigate to draftable.com/compare in your web browser.
  2. Upload the old and new PDF.pdf compare draftable 1
  3. Hit Compare.pdf compare draftable 2
  4. Check the change list online or download the compare report to your machine.pdf compare draftable 3


This platform is built to compare text, image, PDF, Excel even folder. It shows file details, compares 2 PDF by text, image. Another place that Diffchecker shines is that it can OCR text. It highlights the differences in side-by-side view, but it cannot spot the differences as accurately as Draftable.

Compare two PDF files side by side online free with Diffchecker

  1. Navigate to diffchecker.com/pdf-diff/ in your web browser.
  2. Upload the old and new PDFs.
  3. Check the highlighted differences.pdf compare diffchecker


This platform is built to edit, create, convert and organize PDFs. It is a solid option to compare 2 simple PDFs basing on text changes. The max file size PDFForge set for free use is 250MB. It offers side-side or inline view.

Compare 2 simple PDFs online with PDFForge

  1. Navigate to tools.pdfforge.com/compare-pdf in your web browser.
  2. Click Choose File to upload both the old and new PDF.pdf compare pdfforge 1
  3. Hit Compare and check the changes.pdf compare pdfforge 2

Open Source PDF Compare Software to Download

Finally, there is open-source PDF compare software, like KIWI PDF Comparer. It can compare PDFs, Word and Excel documents, graphic Autocad, also prints them to PDF format. There are 2 comparison modes: text and image compare, compare Pixel to pixel, without losing the original PDF formatting.

This program can be installed across Windows, macOS and Linux machines.

However, the free version has limits, you can compare up to 20 pages, and there will be only attribution texts on saved result.

How to compare PDF on Mac or Windows with open source tool

  1. Get the free version of KIWI PDF Comparer, install and fire up the app on your machine.
  2. Import the old and new PDFs to the app, choose a compare mode.
  3. Hit Compare button to spot the differences.kiwi pdf compare
  4. Check the changes or print the changes in PDF format.

When it comes to tools of PDF Compare, from premium one like Adobe Acrobat to free service or software, our post should have the best options covered. But to pick the one suitable that works the best for your, our suggestion is always to try them first on your machine, as free trial or subscription is a common rule to bring the right tool onto our machine.