ComPDFKit PDF SDK 1.7.0 — Compare PDFs

Updates | Content Comparison · Overlay Comparison · Compare Documents Mon. 13 Feb. 2023

This time we updated and released PDF Comparing on macOS and Windows platforms. Two methods to compare PDF files and show the differences are provided by ComPDFKit: content comparison and overlay comparison. These two methods will be explained in detail in the following part. And you will understand which method is right for you. 

ComPDFKit PDF SDK 1.7.0


No matter which method you used to display the comparing results, ComPDFKit supports comparing the text, images, and strokes (tables & graphs are also supported). The different colors can be set to show kinds of changes such as deletions (By default: red, transparency 20%), insertions (By default: green, transparency 20%), and edits (By default: blue, transparency 20%).


  • Show comparison results in original files: This is a method to display two compared files side by side. You can see all the changes in these two original files. It’s often used to compare two similar versions of product plans, contracts, promotion plans, etc.
  • Show comparison results in one file: This method is to combine two comparison files, then show the results in one file. It may be more proper to compare two files with many strokes like construction design papers. The strokes are set with different colors, you can see the stroke color to know the differences in these comparison files.


Content Comparison


Content comparison is often used to quickly find the changes between different PDF versions, and is suitable for files with much text information. The content that can be compared includes text, images, etc. Integrate ComPDFKit into your apps and save your users’ time to work on the work that really matters.


The following picture and code sample show the comparison effects and you can see the deleted, inserted, and edited words are marked by different colors.


Content Comparison by ComPDFKit


Overlay Comparison


Overlay comparison is to superpose two files and show the differences by different colors. The superimposed part shows the mixed color. You can set the page range to compare, color of original files, and the transparency of the strokes. This is usually used to compare files with strokes like architectural drawings.


The following parts are the picture and code sample to show how ComPDFKit works. One of the two architectural drawings is colored green, the other one is colored yellow.


Overlay Comparison by ComPDFKit


Why Compare Documents?


In many industries, people need to deal with file work. Comparing two versions of a PDF file is needed occasionally. 


  • Education: When the teacher checked the students’ papers, and version two was handed in, the teachers could compare the papers and check the modified parts quickly.
  • Finance: It could also be used to compare financial statements and analyze the financial picture.
  • Government: Government paper works are much more than other industries. Public speech papers, policy plans may need to change many times. It could help a lot if they can compare different document versions and find the changes automatically. 
  • Legal: It would be easier to review contracts, legal documents with PDF comparison, when there are many similar large files.
  • Healthcare: It could speed up the process of checking new versions of a patient report or document against previous copies.


More to Come!


You can find more information about comparing PDFs in this blog. Contact us for a free trial.

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