Text Diff — Compare Two Texts Online
Paste two texts to see their differences highlighted inline or side-by-side.
How It Works
- 1Paste the original text on the left and the changed text on the right.
- 2Differences are highlighted line by line as you type.
- 3Copy or share the diff result.
About Text Diff
Need to find the differences between two text blocks? Whether you are comparing two versions of a configuration file, reviewing changes to a document, checking what was modified in a code snippet, or verifying that a migration script preserved content correctly, this tool makes differences immediately visible. Paste two texts into the left and right panels and the tool highlights additions in green, deletions in red, and unchanged text in the default color. Toggle between inline diff mode (additions and deletions shown interleaved in a single view, similar to git diff) and side-by-side diff mode (the two texts shown in parallel columns with aligned changes). The diffing algorithm uses the jsdiff library, which produces clean, minimal diffs that accurately represent the smallest set of changes between the two inputs. This is useful for developers comparing code versions, technical writers reviewing document edits, translators verifying changes between drafts, and anyone who needs to spot differences that are hard to catch by eye.
From the blog
Frequently Asked Questions
Is my data sent to a server?
No. All processing happens locally in your browser. No data leaves your device.
What diff algorithm is used?
The tool uses a standard line-by-line diff algorithm that highlights additions, deletions, and modifications — similar to what git diff produces.
Can I compare code files?
Yes. The diff tool works with any plain text including source code, configuration files, JSON, XML, or prose. Line-by-line comparison makes it easy to spot changes.
What do the colors mean?
Green highlights indicate added lines (present only in the second text), red highlights indicate removed lines (present only in the first text), and unchanged lines are shown without highlighting.
Is my file uploaded to a server?
No. Transmute processes everything locally in your browser using JavaScript and the Canvas API. Your files never leave your device — there is no server, no upload, no cloud processing.
Related Tools
JSON Formatter
Format, validate, and minify JSON with syntax highlighting. Pinpoint syntax errors with precise line numbers — perfect for debugging API responses.
Text Case Converter
Convert text between UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case, and CONSTANT_CASE. One click per format.
Word Counter
Count characters, words, sentences, paragraphs, and estimate reading time. Live updates as you type — perfect for essays, blog posts, and tweets.
Regex Tester
Test regular expressions with real-time match highlighting and capture group inspection. Supports all JavaScript regex flags — global, multiline, and more.