About Duplicate Line Remover
This free online duplicate line remover processes text lists instantly โ removing duplicate lines, sorting alphabetically, trimming extra spaces, removing blank lines and more. It is ideal for cleaning up CSV data, keyword lists, email lists, code imports and any text where repeated entries need to be eliminated.
The case-insensitive option treats "Apple" and "apple" as duplicates. The line numbering option is useful for creating numbered lists. All processing happens in your browser โ no data is sent to any server.
Frequently Asked Questions
What counts as a duplicate line?+
By default, exact duplicates are removed (case-sensitive). Enable "Case-insensitive" to also remove lines that differ only in uppercase/lowercase. Leading and trailing spaces are optionally trimmed before comparison.
Can I use this for cleaning keyword lists for SEO?+
Yes โ paste your keyword list, enable Remove duplicates, Trim whitespace and Remove empty lines, then click Process. Copy the clean list for use in Google Ads, SEMrush or any SEO tool.
How many lines can this tool handle?+
No hard limit. The tool handles large lists efficiently in the browser. Lists with 10,000โ50,000 lines process in under a second on modern devices.
Can I sort numbers correctly?+
The current sort is alphabetical (lexicographic). For pure number lists, alphabetical sort may give 1, 10, 2 instead of 1, 2, 10. A numeric sort option may be added in future updates.
Does removing duplicates preserve original order?+
Yes. The first occurrence of each line is kept in its original position. Later duplicates are removed. Enable Sort A-Z if you want sorted output instead.