Open the Comment Module. Choose the Compare Documents option.
You will need to choose the two versions of your file to compare. Click on the folder icon next to the Original Document (opens on the left) and the Revised Document (opens on the right). These will open a Browse Window for you to find your files.
Pick your page range for each document.
Then click Compare.
You will see this window as Soda PDF sets the files up for comparison.
Your files will open up next to each other showing all the discrepancies between the two.