How to Compare Two Blocks of Text (Diff Checker)
Published September 11, 2026 · 2 min read
Spotting what changed between two versions of a config file, a paragraph of writing, or a code snippet is much easier with a proper diff than by eye. This tool lines up two texts and highlights every addition and removal.
Try Diff CheckerSteps
- 1
Open the Diff Checker tool
Go to the text diff checker.
- 2
Enter your original text
Paste the first version.
- 3
Add a separator line and the second version
Add a line with only --- between the original and the updated text.
- 4
Review the differences
Added and removed lines are clearly marked.
Frequently asked questions
Line by line — each line is matched against the other version, with added and removed lines marked individually.
Very long texts (over roughly 3,000 lines per side) are capped to keep the comparison fast and responsive in your browser.
Yes, indirectly — extract the text from each PDF first with PDF to Text, then paste both into this tool; or use the dedicated Compare PDF tool which does this automatically.
Because the comparison runs instantly and locally, this is a fast way to review changes without pasting sensitive text into an online diff tool of unknown origin.