Text Diff Checker
Compare two pieces of text and find the differences.
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Quick Tip
Paste the original text into the first box.
About This Tool
Why use Text Diff Checker?
Paste two versions of a text and see which lines were added, removed or left unchanged. The comparison uses a longest-common-subsequence diff — the same approach as version control — so inserting a line at the top does not mark everything below it as changed.
Removed lines are marked with a minus, added lines with a plus, and unchanged lines are shown for context. It compares whole lines, so a one-word edit shows as one line removed and one added; that is the standard way diffs are presented in code review.
Key Benefits
Proper line diff
Insertions and deletions are detected as such instead of shifting every following line.
Context preserved
Unchanged lines stay visible, so you can see where a change sits.
Works on any text
Code, config, prose or CSV rows — anything with lines can be compared.
How to use Text Diff Checker
- 1
Paste the original text into the first box.
- 2
Paste the changed version into the second.
- 3
Read the diff: − for removed lines, + for added lines.
- 4
Copy or download the diff to attach to a ticket or a review.
Best use cases
Compare two versions of a config file.
Check what an editor changed in a document.
Spot differences between two API responses.
Review a contract or policy revision line by line.
Text Diff Checker FAQs
How does the comparison work?
It finds the longest sequence of lines common to both texts and marks everything else as added or removed, which is how git and similar tools present a diff.
Does it highlight changes within a line?
No, the comparison is line by line. A changed line appears as one removal plus one addition.
Is whitespace significant?
Yes. Trailing spaces and indentation changes make lines different, which is usually what you want when comparing code or config.
Is my text uploaded?
No. The comparison runs in your browser, so both versions stay on your machine.
Related Developer Tools
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