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How to see what changed in a document

Somebody sends back a contract and says they made a couple of small changes. Reading forty pages twice to find them is how people end up signing a clause they never agreed to. This reads both documents and tells you which pages differ and what the difference was.

1. Drop both versions on the box at the top. You can drop the two together or one after the other.
2. Check the labels: the first one you added is marked Before, the second After. Start again if they are the wrong way round.
3. Press Compare them, and wait while both are read. The line underneath counts the pages as it goes.
4. Look down the list. The pages marked unchanged can be skipped.
5. For each changed page, read the Was and the Now lines under it.

What is compared, and what is not

The words are compared, line by line, page by page. A line that is the same in both is passed over; a line that was taken out and a line that was put in are shown to you. Pages added at the end of the newer document, or dropped from the older one, are named as such.

What is not compared is the look of the page. A word turned bold, a colour changed, a picture swapped, a margin moved - none of that shows up here, because none of it changes the words. This tool answers "what does it say now that it did not say before", which is the question that matters on a contract, an invoice or a policy.

Scans cannot be compared

If a document is a photograph of paper rather than a document with text in it, there are no words to read and nothing to compare. You are told plainly when that happens rather than being shown an empty result. Reading words out of a picture is a separate job, called OCR, which this site does not do yet.