Compare PDFs

Compare two PDF files online and see every change highlighted in red, page by page.

100% Free No installation required Secure & private

Trusted by

Rate this tool

0/5 · 0 votes

Every metadata app in one place

Ten apps for reading, editing, removing, extracting and comparing what is hidden inside your files.

See all metadata apps Open Workspace

Compare PDF at a glance

What the app does with your two documents, before you add anything.

2 PDF files per comparison, the original and the changed one

3 ways to read the result: slider, side by side, and diff

0 credits used. Comparing a PDF is free and needs no account

1 report you can download, with a diff image for every page

See what changed between two PDF files

Compare two PDF files and the app renders every page of both documents, then checks the pages against each other pixel by pixel. Changed areas are painted red over a faded copy of the page, so a moved stamp, a new paragraph, or an edited figure stands out at a glance.

The result opens as a list of page pairs. Pick any page from the thumbnail rail and the viewer shows that pair on its own, with the red overlay in place.

Rendering noise is ignored on purpose, so the soft edge of a letter does not register as a change. What is left on screen is the difference you were looking for.

Input format: PDF. Two files per comparison, one as the original and one as the changed document.

Compared page by page, in the same position on each page.

Score every page and catch added or removed pages

Every page pair carries its own difference score, from 0 for a page that did not move to 100 for a page that is completely different. Pages are labelled Identical, Changed, Added in B, or Removed from A, so a long document can be worked through by score instead of by eye.

A page that exists in only one of the two PDF files is not skipped. It is tinted green when it is new in the second document and red when it is gone from the first, and it is counted as a full change.

The two documents do not have to hold the same number of pages. The comparison runs over the longer of the two and reports the extra pages instead of turning the job down.

Added in B: a page only in the second PDF. Removed from A: a page only in the first. Changed: in both, but not the same.

Compare a PDF inside your browser

A PDF you pick from your own device is compared inside the browser. Both documents are opened and drawn on the page you are already on, so the file itself does not have to travel anywhere to be read.

A PDF you bring in from a link, from Dropbox, or from OneDrive is fetched over the network first. Every transfer runs over an encrypted connection, the processing is fully automated, and no person reads or copies your documents.

Your files are not used to train AI models, and you keep the copyright and the ownership of both PDFs at all times. The servers behind the service are in Europe.

Both PDF files are opened and compared directly in the browser tab.

What the PDF comparison covers

This app compares how two PDF files look. Here is what that includes, and what it does not.

What you are looking for	Covered	How it is shown
Visual changes on a page	Yes	Marked in red
A page added in the second file	Yes	Tinted green
A page missing from the first file	Yes	Tinted red
How much a page changed	Yes	A score out of 100
A copy of the result to keep	Yes	A report PDF
Word by word text changes	No	Not a text comparison
Word, Excel, or PowerPoint files	No	PDF files only
A password protected PDF	No	Remove the password first

This is a visual comparison. Both PDF files are rendered as pages and checked page by page, so a change is marked where it sits rather than listed as text. Neither document is altered, and to compare other file types there are separate apps for images and for video.

When a PDF comparison helps

Three jobs where two versions of the same document arrive without a list of what changed.

Contract revisions

A contract rarely comes back with a change list attached. Compare the two PDF files and each edited clause is marked on the page it sits on.

Invoices and statements

Two versions of one invoice can differ by a single figure. The page score points at the page that moved and the red overlay points at the line.

Reports and drafts

A long report goes through many rounds. Compare the PDF you sent with the PDF that came back and read only the pages the score says changed.

How to compare two PDF files

Upload

Upload the first PDF file as the original document.
Add the second PDF

Upload the second PDF file as the changed document.
Compare

Start the comparison. Both PDF files are rendered and checked page by page.
Review

View the result pages and look for differences marked in red.
Save

Save or export the result if you want to keep a record of the changes.

Compare PDF FAQ

How can I compare two PDF files?

Add the original PDF as the first file and the changed PDF as the second, then start the comparison. Both documents are rendered page by page and every difference is marked in red on the page where it appears. There is nothing to install and no account to open.

Is it free to compare PDF files here?

Yes. Comparing two PDF files is free and no account is needed. Add both documents, start the comparison, and read the result.

Does the PDF comparison show text changes?

Not as text. The app compares how the two PDF files look, page by page, so it marks the area where a paragraph changed rather than listing the words that changed. There is no text extraction and no character recognition behind it, which is why a scanned page and a digital page are treated the same way.

Can I compare PDF files with a different number of pages?

Yes. The comparison runs over the longer of the two documents. A page that appears in only one file is tinted green when it is new and red when it is gone, labelled Added in B or Removed from A, and counted as a full change.

Do you need Acrobat Pro to compare two PDFs?

Not for this. Acrobat has its own compare feature behind a paid plan. Comparing two PDF files here runs in the browser, costs nothing, and needs no software on your computer.

Can ChatGPT compare two PDFs?

That depends on the assistant and is outside what this page can answer for you. What this app does is fixed and repeatable: it renders both PDF files, checks each page pair, marks the changes in red, and gives every page a score you can check yourself.

Is it private to compare PDF files online?

A PDF you pick from your own device is compared inside the browser, so the document does not have to travel anywhere. Anything you bring in from a link or from cloud storage moves over an encrypted connection. The processing is automated, nobody reads your files, and they are never used to train AI models.