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Text Diff Checker
Compare two texts or code snippets and see every difference. Free, private, and 100% in your browser.
Original Text
Modified Text
Differences
Paste text into both editors to see the differences.
Compare Text Online
A diff checker shows what changed between two versions of a text. Paste the original on the left and the new version on the right: added lines are green, removed lines are red, and the changed words inside a line are highlighted. It is ideal for code reviews, comparing configuration files, spotting changes in contracts and documentation, and finding what differs between two log files.
--- original.txt
+++ modified.txt
@@ -2,3 +2,3 @@
1. Update the version number
-2. Deploy on Tuesday
+2. Deploy on Thursday
3. Publish the release notesFeatures
Side-by-side and unified views
Read changes in two aligned columns, or in a single column like git diff.
Word-level highlighting
Inside changed lines, the exact words that were added or removed are highlighted.
Ignore case and whitespace
Skip changes in indentation, trailing spaces, or capitalization to focus on real edits.
Unified patch export
Copy or download the changes as a .diff file that works with git apply and patch.
Large inputs
Compare thousands of lines with the Myers diff algorithm, the same one used by Git.
Private by design
Both texts are compared in your browser. Nothing is uploaded or stored.
How to Compare Two Texts
- Paste or upload the original text in the left editor.
- Paste or upload the changed text in the right editor.
- Read the differences below, in side-by-side or unified view.
- Optionally ignore case or whitespace, or switch to Patch to download a .diff file.
Frequently Asked Questions
Is my text uploaded when I compare it?
No. The comparison runs entirely in your browser, so it is safe for source code, configuration files, contracts, and logs that contain private data.
How does the diff checker find differences?
It splits both texts into lines and uses the Myers diff algorithm to find the smallest set of added and removed lines. Changed lines are then compared word by word to highlight exactly what changed.
Can I ignore whitespace or indentation changes?
Yes. Enable Ignore whitespace to treat lines as equal when they differ only in spaces, tabs, or indentation. Enable Ignore case to ignore capitalization.
What is the Patch view?
It shows the differences in unified diff format, the standard output of diff -u and git diff. You can download it as a .diff file and apply it with git apply or patch.
Can I compare JSON or XML?
Yes, but our JSON Comparer and XML Comparer are better for structured data: they ignore formatting and key order and list every changed value by path.
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