Diff Checker
WEBCompare two blocks of text and instantly highlight every added, removed, and unchanged line or word — free and in your browser.
Type or paste text in both panes to see the differences.
What is the Diff Checker tool?
This diff checker compares two texts side by side and highlights exactly what changed — additions in green, deletions in red, untouched content left plain. Paste the original on one side and the changed version on the other, and the differences appear instantly. It is free, has no limits, and runs 100% in your browser: your text is never sent to a server, which matters when you are comparing contracts, translations, customer data or proprietary code.
Two comparison modes cover the two jobs people actually have. Line mode compares line by line — ideal for code, config files and logs, where a code diff checker needs to respect line breaks. Word mode highlights the changed words within each line — ideal for prose, contract revisions and copy edits, where you want to see precisely which phrases moved. Turn on ignore whitespace to skip indentation noise, use swap to flip which side is the baseline, and read the running summary of added and removed segments. When you need to share the result, copy it as a clean unified diff for a review, ticket or commit message.
Because the comparison is local, the tool works on a phone as comfortably as a desktop, keeps working offline once loaded, and handles Arabic and other right-to-left text correctly. No sign-up, no upload, no caps — just paste two texts and see the difference.
How to use the Diff Checker
- Paste the original text into the first pane.
- Paste the changed text into the second pane.
- Choose line comparison for code and logs, or word comparison for prose.
- Toggle ignore whitespace if indentation noise gets in the way.
- Read the highlighted differences and the added / removed summary.
- Copy the unified diff to paste into a review, ticket or commit message.
Frequently asked questions
Is my text uploaded anywhere?
No. The entire comparison runs locally in your browser — neither text is ever sent to a server, and there is nothing stored remotely to delete. That makes it safe for contracts, unpublished writing, customer data and proprietary code.
How do I compare two texts online?
Paste the first version into one pane and the second into the other — the differences are highlighted immediately, with a summary of what was added and removed. There is no sign-up and no file size cap.
How is this different from Diffchecker.com?
The result looks similar — a side-by-side highlighted diff. The difference is where the work happens: with many online diff services the text is processed on their servers, and offline privacy is part of a paid desktop product. Carbide's comparison runs entirely in your browser, free, so private text never leaves your device.
What is the difference between line and word comparison?
Line mode compares the texts one line at a time and is best for code, configuration and logs where line breaks matter. Word mode compares word by word within each line, which is better for prose and copy edits where you want to see exactly which words changed.
Can I compare two files?
Yes — open each file, copy its contents and paste one per pane. Because the tool has no size limits and processes locally, even long documents and large source files compare quickly.
What does ignore whitespace do?
It skips differences that are only spaces, tabs or indentation, so two files that differ only in formatting show as equal and you can focus on real content changes — especially useful after reformatting code.
Is the diff checker free?
Yes, completely — no sign-up, no premium tier and no limits on length or number of comparisons.
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