Duplicate Line Remover
Remove duplicate lines and keep only unique entries
How to Remove Duplicate Lines
- Paste text with duplicate lines
- Choose removal mode (keep first, keep last, remove all)
- View deduplicated output with count of removed lines
- Copy the unique lines
Duplicate Remover Features
- Keep First Occurrence: Preserve the first instance of each duplicate
- Keep Last Occurrence: Preserve the last instance of each duplicate
- Remove All Duplicates: Delete all lines that appear more than once
- Case-Sensitive Options: Control case handling
- Shows Removal Count: See how many duplicates were found
- 100% Free: No limits on text length or usage
Why Remove Duplicates?
Duplicate lines create data quality issues. In contact lists, duplicate emails cause double-sends and annoy recipients. In code, duplicate imports waste space and slow compilation. In datasets, duplicates skew analysis results.
Example: You scraped 1000 product listings but many are duplicates. Removing duplicates before importing to your database prevents constraint violations and ensures each product appears once. Or you have a list of 500 email addresses with 50 duplicates—cleaning prevents sending the same newsletter twice to the same person.
Use cases: Cleaning scraped data, deduplicating email lists, preparing unique values for databases, consolidating log files, ensuring dataset uniqueness before analysis, and removing duplicate entries from CSV imports.
Privacy & Security
All duplicate removal happens locally in your browser. Your text is never uploaded to servers, stored, or logged. The processing uses JavaScript, keeping your data completely private.