How to see earlier versions of a saved PDF

Choose File > Earlier versions in PDF by Zaweba. If the PDF was saved incrementally, each of those saves opens in a tab of its own, so you can see the document as it stood at each point and compare it with the current one.

This works because of how PDFs can be saved. An incremental save doesn't rewrite the whole file; it adds the changes to the end, leaving the earlier content in place underneath. The older states of the document are still in the file, and the app can show them to you.

When it is useful

Signed documents are a common case. Signing a PDF usually adds an incremental save, and if more changes are made after the signature, looking at the earlier version shows exactly what was signed.

Forms are another. A form filled in, saved, then changed and saved again carries both sets of answers, and Earlier versions shows you what was there first.

And sometimes it's simply a rescue. If someone saved over a version you needed, and the saves were incremental, the older state may still be there to look at.

Opening the earlier saves

Open the PDF and choose File > Earlier versions. Each earlier save opens in its own tab, alongside the current document. Switch between the tabs to see each state.

If you want to keep an older version as a file of its own, save it from its tab under a new name. Then you have a clean copy of that version that won't change.

Seeing exactly what changed

Flicking between tabs shows the general picture. For a precise answer, use File > Compare files: open the newer version and compare it with the older one. The app marks words changed, added or removed, formatting changes such as font, size and colour, and pictures added, removed, moved or resized, side by side with the two documents scrolling together. You can save the result as a PDF report.

Limits and privacy

Not every PDF has earlier versions. A file saved in full each time, or one that has been through a program that rewrites the whole file, keeps only its latest state. If Earlier versions finds nothing, that's the reason.

Remember it works in both directions. If you are about to send a PDF to someone outside your organisation, earlier states inside it can show text you have since changed. That's worth knowing before you share. Tools > Actions has steps to remove hidden information and sanitise a file, and the built-in Prepare for distribution action is designed for exactly this moment.

Don't confuse it with undo. Within one editing session, Ctrl+Z steps back through named changes, and Revert to saved returns to the file as it was last opened or saved. Earlier versions is about what's stored in the file across saves, not about the session you're in now.

A record of what a file said

Earlier versions sits with the app's other document tools, such as Document properties, metadata and security settings. It's one of those features you rarely need, but on the day you do, it can settle an argument about what a document said and when. Like everything in PDF by Zaweba, it works offline on your own PC.