How to compare two texts and see what changed
Did a colleague change anything in the contract? Which line differs between two config files? Text diff compares line by line.
Steps
- Paste the original text on the left.
- Paste the changed text on the right.
- Read the result: lines starting with
+were added, lines starting with-were removed, and unchanged lines are shown as context.
Making comparisons cleaner
- JSON: run both through JSON formatter with Sort keys ticked, so key order and spacing do not cause false differences.
- Case or wording noise: normalise both with Case converter when only capitalisation changed.
- Whole-paragraph edits: a changed line appears as one removal and one addition, because comparison is by line, not by word.
Tips
- Large unchanged sections are not a problem; the tool trims matching start and end lines first.
- Trailing spaces and different line endings can show up as differences. Remove them if they are not meaningful.
- For PDFs, extract the text with PDF to text first and compare the two text files.
Limits
It compares plain text only. It does not understand formatting, tables or images, and very long inputs (tens of thousands of lines) may be slow.