How to compare two versions of a PDF
Open Compare, add the older version first and then the newer one, and press Compare them. The newer file comes back with every change marked.
CompareFree. Nothing is uploaded.
How to do it
- Open Compare.
- Add the older version first, then the newer one.
- Press Compare them.
- Open the marked copy: new words are highlighted in green, and a comment marks each place words were taken out.
What it compares
Words, not pictures or layout. A paragraph that moved does not make everything after it look changed. Fonts, spacing and images are not compared.
Good for
A rent agreement or offer letter that came back revised, a contract after the other side’s edits, a policy document with a new version. Reading two long versions side by side is slow and easy to get wrong; a word-by-word comparison misses nothing. Read the marked copy in any PDF reader, or in Read, which lists the comments so you can step through each removal.
Scanned versions
A scan has no words to compare, only pictures of them. Run each version through Make searchable first, then compare the results. To add your own notes to the marked copy, use Mark up.
Order matters. Add the older version first: the newer one is the file that comes back marked, so green always means added since the older version, and a comment always means taken out.
A worked example
Your landlord sends a revised rent agreement. Open Compare, add your copy of the old agreement first, then the revised one, and press Compare them. Open the marked copy: a new rent and a new notice period are highlighted in green, and comments mark where the old figures were. Step through them with the comments list in Read, and raise anything you did not agree to before you sign.
Both files you added stay exactly as they were; the marked copy is a new file beside them, so nothing is overwritten.
What it will not catch
Comparing words means some changes pass unmarked: a signature or stamp added as a picture, a changed logo, bold text made plain, or a table rearranged without changing its words. For those, look at the two versions side by side. If either version is a scan, its words must be read first, and any misreading will show up as a change that is not really there.
Line breaks and page breaks do not count as changes either, so a paragraph that only flowed onto the next page is not marked. That keeps the marks to what someone actually rewrote.
Common mistakes
Adding the files the wrong way round, so additions show up as removals: the older one always goes first. Comparing a scan with a typed version without making the scan searchable. And treating the marked copy as the new agreement: it is a working copy with marks on it, so sign the clean revised file, not the marked one.
Questions people ask
Are my documents uploaded?
No. Both are read and compared in your browser.
Can I compare more than two files?
Two at a time: the older, then the newer.
Does it change the newer file?
No. You get a new, marked copy; both files you picked stay as they were.
Does it notice a changed number, like a rent amount?
Yes. Numbers are words too: the new amount is highlighted and a comment shows the old one.
Is the marked copy safe to send to the other side?
Yes. It is the newer file with highlights and comments added; nothing else on its pages changed. Say in your message that green means added and the comments show what was taken out.
Can I compare a Word file with a PDF?
Turn the Word file into a PDF first with Word or Excel to PDF, then compare the two PDFs.
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