Text Diff is a free tool for comparing two blocks of text or code line by line. It uses the LCS (Longest Common Subsequence) algorithm for accurate diffs and highlights word-level changes within modified lines. Perfect for code reviews, config file comparisons, and document version tracking.
Three steps to a clear, color-coded text comparison.
Enter the original text in the left panel and the revised version in the right. Works with source code, prose, configuration files, or any plain text.
Choose whether to ignore whitespace or compare case-insensitively, then click Compare. The tool performs a line-by-line diff of both inputs.
Additions are highlighted in green, deletions in red, and modifications in yellow. Scroll through the synchronized panels to review every change in context.
Paste the old and new versions of a function or file to review your changes before running git commit. Catch accidental deletions or leftover debug lines.
Compare two SQL queries side by side to spot the typo or missing JOIN clause that's causing different results. Useful when queries are long and visually similar.
Diff log outputs from two different runs to pinpoint where behavior diverged. Helpful when debugging intermittent failures or comparing stdout across environments.
Compare draft and published versions of READMEs, runbooks, or API docs to verify that all intended edits are present and no sections were accidentally removed.
Paste your original text in the left panel and the modified text in the right panel, then click Compare. The tool highlights added, removed, and changed lines side by side. You can also enable options to ignore whitespace or case differences.
A text diff (also called a 'unified diff' or 'patch') is a comparison that shows exactly which lines were added, removed, or changed between two versions of text. It's widely used in software development, document review, and content editing to track changes.
Yes. All comparison processing happens entirely in your browser. Your text is never uploaded to any server, making it safe for comparing confidential documents, source code, and private content.
Absolutely. The text diff tool works with any plain text — source code, configuration files, log files, SQL queries, markdown, and more. It compares line by line and highlights additions, deletions, and modifications just like a code review tool.
This tool provides the same comparison logic as command-line diff, but with a visual, color-coded side-by-side interface that's easier to read. There's nothing to install — just paste your text and compare instantly in your browser.
Yes. Use the provided options to ignore leading/trailing whitespace, blank lines, or case differences. This is useful when you want to focus on meaningful content changes rather than formatting.