Does it compare every page visually at once?

No. Visual comparison focuses on one page per run; text comparison covers complete documents.

What does the percentage mean?

It is the share of compared rendered pixels above the colour-difference tolerance.

Can font rendering create differences?

Yes. Anti-aliasing and changed page dimensions can affect pixels.

Does it explain wording changes?

No. It reports whether extracted text differs but does not produce a semantic text diff.

What if one PDF has fewer pages?

The visual check uses the last page shared by both files for an out-of-range request.

PDF Tools

Compare PDFs

Compare two PDF files with original, changed and visual-difference previews.

Free browser toolRuns in your browserNo sign-up

PDF comparison studio

Compare visual pixels and extracted text

Inspect one page side by side, highlight changed pixels and separately check whether selectable text differs anywhere in the files.

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files ready

Page 1

visual check

Pending

pixel change

Original PDFChoose a PDF fileClick to browseChanged PDFChoose a PDF fileClick to browse

Choose both PDFs and compare them to open the original, changed and visual-difference previews.

Pixel differences can include anti-aliasing, font rendering and page-size changes.

About the Compare PDFs

Compare PDFs renders one requested page from two files and shows original, changed, and red difference views. It also compares the extracted selectable text across the complete documents.

The visual percentage measures rendered pixels whose colour difference passes a tolerance. Anti-aliasing, font rendering, page-size changes, and shifted content can produce differences even when wording appears similar.

The requested visual page is clamped to the last page available in both files, while the text flag covers all pages. Comparison is local and does not create an output PDF.

Key features

Original and changed PDF inputs
Selectable visual page number
Three-way original, changed, and difference preview
Changed-pixel percentage
Whole-document selectable-text comparison
Source file-size display
Local browser comparison

How to use

1Choose the original PDF and the changed PDF.
2Enter the page number to inspect visually.
3Run the comparison and review all three previews.
4Use the pixel percentage as a locator, not a semantic verdict.
5Check the whole-document text status and inspect other pages as needed.

Examples

Check a revised proposal

Input: Original and revised PDFs, page 4

Output: Three previews, pixel-change percentage, and whole-file text status

Frequently asked questions

Does it compare every page visually at once?: No. Visual comparison focuses on one page per run; text comparison covers complete documents.
What does the percentage mean?: It is the share of compared rendered pixels above the colour-difference tolerance.
Can font rendering create differences?: Yes. Anti-aliasing and changed page dimensions can affect pixels.
Does it explain wording changes?: No. It reports whether extracted text differs but does not produce a semantic text diff.
What if one PDF has fewer pages?: The visual check uses the last page shared by both files for an out-of-range request.

Open a related tool to prepare your files or refine the finished result.