Text Diff Checker
Compare two blocks of text, configuration files, or code snippets side-by-side to highlight exact insertions, deletions, and modifications at the line, word, or character level — processed 100% locally in your browser.
How to Use Text Diff Checker
- 1Paste the original version of your text or code into the left ('Original Text') box.
- 2Paste the revised version into the right ('Modified Text') box.
- 3Select your comparison granularity (Lines, Words, or Characters).
- 4Inspect the color-coded diff output where green highlights additions and red highlights removals.
Frequently Asked Questions
Is it safe to compare confidential contracts or private source code here?
Yes. The diff algorithm runs entirely in your browser tab using client-side JavaScript. Neither text block is ever uploaded or logged.
When should I use Word diff vs. Line diff?
Line diff works best for source code, JSON, and config files where changes happen line-by-line. Word or Character diff is better for prose, legal clauses, and paragraphs where a single word changed inside a long sentence.
What do the green and red highlights mean?
Red (with strikethrough or minus indicators) marks text that was present in the original version but removed, while green marks new text added in the modified version.
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