Compare PDF – Spot Text Changes Between Versions

Upload the original and the changed PDF to see which lines were added or removed. The comparison runs in your browser, nothing is uploaded.

  • ✓Files never uploaded
  • ✓No file limits
  • ✓No sign-up
  • ✓No watermark

How to Compare PDF

  1. 1Add the original PDF on the left and the changed PDF on the right.
  2. 2Click Compare PDFs.
  3. 3Review the highlighted added and removed lines.
  4. 4Download the report as a .txt file if you want to keep it.

Why pdfdots?

Private by design

All processing happens locally in your browser. Your documents are never uploaded to a server, so nobody else can see them.

No limits

No daily task caps, no file-count limits and no premium tier. Process as many PDFs as your device can handle.

Fast

There's no upload or download queue. Work starts the moment you drop a file and finishes at the speed of your own computer.

Works everywhere

Windows, Mac, Linux, iPhone, Android or Chromebook — if it has a modern browser, pdfdots runs on it. Nothing to install.

See what changed before you sign

Reading two versions of a contract side by side and hoping to spot the difference is how small but expensive changes slip through. Compare PDF does the tedious part for you. It extracts the text from both files, compares them line by line and highlights every line that was added in the new version or removed from the old one. A short summary tells you how many lines changed, and you can download the whole result as a plain text report.

We use it for contracts that come back from the other side, updated terms of service, revised price lists and thesis drafts. It is especially useful when a sender claims nothing important changed: now you can check in seconds.

It helps to know what the tool compares. It looks at text only. Changes to images, logos, colors or the visual layout will not appear, and a line that merely moved to a different place may show up as removed in one spot and added in another. Scanned PDFs have no text to compare, so run OCR PDF on them first. Both files are processed in your browser and never uploaded, which matters when the documents are confidential.

Our take

We compare PDFs when a counterparty sends back "the same contract, just a few small fixes", when a new version of terms and conditions appears, or when we want to know what really changed between two drafts of a report.

We always put the older file on the left and the newer one on the right, so added lines really mean new text. Then we download the report and keep it with the signed version, which has saved us more than one discussion later.

The pitfall: this is a text comparison. A swapped logo, a moved image or a changed color will not show up, and a scanned PDF needs OCR PDF first before there is any text to compare.

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Frequently asked questions

Are my PDFs uploaded?+

No. Both files are compared entirely in your browser and never leave your device.

What exactly is compared?+

The extracted text, line by line. Added lines and removed lines are highlighted.

Does it detect changes in images or layout?+

No. It compares text only, so a new logo, a moved picture or a color change is not reported.

Can I compare scanned PDFs?+

Run OCR PDF on both scans first so they have a text layer, then compare them.

Can I save the result?+

Yes. Download the report as a .txt file with all added and removed lines.

Is it free?+

Yes. No sign-up, no watermark and no daily limit.