Compare PDF
Seeing visible changes on corresponding pages of two PDFs.
This is a pixel-based visual comparison, not a semantic or legal review. Font rendering, page dimensions and scan noise can also cause differences. Extra pages are mentioned in the report
How to use Compare PDF?
The function of Compare PDF is to see visible changes in the corresponding pages of two PDFs. This facility is provided in a separate page on PDF Saathi Hub so that you can read the correct input, output and required limits. The method written below is according to the actual tool's behavior, there is no guarantee of perfect conversion or approval.
Steps and output
Select two files and press Compare. You will get red difference preview of every common page, along with text report and combined difference PDF Result: difference PNGs, report and PDF. Set aside a safe copy of the original file before starting work. Selecting the wrong page or version may require rework, so match the file name and content first. Start with a small sample first. Do not close the tab while the tool is running. If you see an error, read it; Do not consider getting incomplete results as success.
Where is caution necessary?
This is a pixel-based visual comparison, not a semantic or legal review. Font rendering, page dimensions and scan noise can also cause differences. Extra pages are mentioned in the report. After downloading, open the new file in a separate viewer. Match page count, orientation, small text, names, dates and important numbers with the original document. Mere downloading of the file is not proof of correct result. If the output is to be sent to a government form, office, school or customer, also check the current file-size and format requirements of that place. If important information has been cut out, appears too light or is misplaced, recreate it from the original.
Privacy and safe use
In this tool, document processing happens in your browser. The file and password are not sent to any conversion server. For the first time, internet is required to download engine files; OCR language data is also downloaded. Ads, chat and translation are separate online features of the site. Putting a private document into AI chat or translation is not the same as local PDF processing. Work only after reading the limits given on this page. Browser memory is different on every device, so no fixed speed or guaranteed result can be given for very large files. Download the new file after processing. Complete the test before replacing the original. Change someone else's document only if you have their permission.
Frequently asked questions
Does it compare the meaning of the words?
No. It compares the pixels of page images.
Will the original file be changed?
No. Save the new output copy separately. Keep the original safe and read it before sending the final result.
What if an error occurs on a large file?
Try with a smaller sample or fewer pages. If memory is less then run it on another device. Do not use incomplete output after error.