What Is a Diff Checker?
A diff checker compares two versions of text and highlights the differences — additions, deletions, and modifications — line by line. It's the same concept behind Git diffs, but accessible in your browser.
Why Compare Text?
Code review — spot changes between file versions
Configuration auditing — find what changed in config files
Content editing — track changes in documents
Debugging — compare expected vs actual output
Merging — identify conflicts before merging changes
How to Use the Diff Checker
Open the [Diff Checker](/tools/diff-checker)
Paste the original text in the left panel
Paste the modified text in the right panel
Click "Compare" to run the analysis
View color-coded results: green (additions), red (removals)
Reading the Diff Output
Green lines — new content that was added
Red lines — content that was removed
Unchanged lines — content that's the same in both
Summary — total count of additions, deletions, and unchanged lines
Use Cases
Before and After Code Changes
Compare your code before and after refactoring to ensure nothing was accidentally removed.
Database Migration Scripts
Compare old vs new schema definitions.
API Response Changes
Detect differences between API versions.