Text Diff
Compare two blocks of text and highlight added, removed, and unchanged lines side by side.
Frequently Asked Questions
diff command. It finds the largest set of unchanged lines and marks the rest as added or removed.+) are present in the modified text but not in the original. Lines in red (prefixed with −) were in the original but removed. Unchanged lines are shown without color.git diff and the Unix diff utility.How It Works
Paste Both Versions
Enter the original text in the left panel and the revised version in the right panel. The diff updates in real time as you type.
LCS Algorithm
The tool uses a Longest Common Subsequence (LCS) algorithm — the same basis as Unix diff — to identify the minimal set of added and removed lines.
Color-coded Output
Green lines are additions (+), red lines are removals (−), and neutral lines are unchanged. A summary shows total added/removed/unchanged counts.
Common Use Cases
Document Version Comparison
Compare drafts of contracts, reports, or articles to see exactly what changed between versions, without relying on tracked changes in Word.
Code Review
Quickly compare two versions of a configuration file, script, or snippet outside a full IDE, or before committing to version control.
Translation QA
Compare source and translated strings line by line to verify all segments are present and no lines were accidentally skipped or duplicated.
Editing & Proofreading
Show editors the exact changes made to an article draft. Line-level diff makes it easy to accept or reject individual changes.
Config File Auditing
Compare production and staging config files to find environment-specific differences that could cause deployment bugs.
Plagiarism Spot-check
Compare a submitted piece against an original source to find copied or lightly rephrased passages before publishing or grading.
