Duplicate Line Remover
Remove duplicate lines from your text instantly. Keep only unique lines with flexible options.
About Duplicate Line Remover
The duplicate line remover is perfect for cleaning up lists, data exports, email lists, word lists, and any text data with repeated entries. It processes your text entirely in the browser — no data is sent to any server.
How to Use
- Paste your text (with one item per line) into the input field.
- Choose your options: case-sensitive comparison and whitespace trimming.
- The output is updated in real-time as you type.
- Check the stats below to see how many duplicates were removed.
- Click "Copy" to copy the clean output.
How It Works
The tool splits your input by line breaks, optionally trims leading/trailing whitespace from each line, then uses a Set data structure to track seen lines and filter out duplicates. Case-insensitive mode converts all lines to lowercase for comparison before deduplication.
FAQ
With case-sensitive enabled, "Apple" and "apple" are treated as different lines and both kept. With it disabled, they are treated as duplicates and only the first occurrence is kept.
Yes. The first occurrence of each line is kept and its position is preserved. Subsequent duplicate occurrences are removed.
Empty lines are also deduplicated. If trimming is enabled, lines containing only spaces are treated as empty. Multiple blank lines will be reduced to one blank line.