Diff Checker
Paste two versions of text to instantly see what changed. Line-level and word-level diff modes with colored highlights for additions and deletions. Copy the diff output with one click.
How to Use the Diff Checker
- Paste the original text in the left panel
- Paste the modified text in the right panel
- View additions highlighted in green and deletions in red
- Toggle between line-level and word-level diff modes
- Copy the diff output with one click
What Is a Diff?
A diff is a comparison between two texts that highlights exactly what was added, removed, or changed. Diff algorithms like Myers and patience diff work by finding the longest common subsequence between inputs, then marking everything else as an insertion or deletion.
Diff tools offer line-level comparison for structural changes and word-level comparison for fine-grained edits within a single line. Whether you are reviewing code, tracking document revisions, or auditing configuration files, a visual diff makes it easy to spot every change at a glance without reading both versions in full.
Common Use Cases
Code Review
Compare file versions before and after changes to verify that only intended modifications were made in a pull request.
Document Versioning
Track revisions between drafts of contracts, proposals, or articles to see exactly which sentences were rewritten or removed.
Configuration Changes
Audit server or application config file updates to catch unintended modifications before deploying to production environments.
Contract Comparison
Highlight differences between original and revised legal agreements so stakeholders can review only the clauses that changed.
Tips for Effective Diff Comparison
Write Meaningful Commit Messages
Describe why a change was made so future diffs have context, not just raw additions and deletions without explanation.
Review Before You Merge
Always inspect the full diff one final time before merging branches to catch last-minute issues or accidental leftover code.
Mind Whitespace Sensitivity
Toggle whitespace visibility when comparing code to distinguish meaningful indentation changes from insignificant trailing space edits.
Choose Unified or Split View
Use unified view for quick scanning of small changes and split side-by-side view when comparing large files with many edits.