Duplicate Line Remover
Remove duplicate lines from text with flexible options.
Clean up lists by removing duplicate lines
The Duplicate Line Remover takes a block of text and removes any lines that repeat, keeping only the first occurrence of each unique line. It is ideal for tidying up lists such as email addresses, keywords, URLs, names, log entries, or any data where the same value should appear only once. Instead of scrolling through a long list by hand, you get a deduplicated version in a single click.
The tool preserves the original order of your lines, so the first time a value appears is where it stays. This is useful when sequence matters and you do not want your list reshuffled or alphabetised.
How to use it and what the options do
Paste your text into the input box, with one item per line. Adjust the three options to match your data, then click Remove Duplicates. A summary shows the total number of lines, how many were removed, and how many remain, and the cleaned result appears in the output box ready to copy.
"Case sensitive" controls whether differences in capitalisation matter; with it off, "Apple" and "apple" are treated as the same line. "Trim whitespace" strips leading and trailing spaces before comparing, so lines that differ only by stray spaces are caught as duplicates. "Remove blank lines" deletes empty lines entirely, which is handy for compacting a list that has gaps.
Tips and privacy
If your list is not deduplicating the way you expect, check the case sensitivity and trim settings first, since hidden differences in capitalisation or spacing are the most common reason near-identical lines survive. For most plain lists, turning off case sensitivity and keeping trim whitespace on gives the cleanest results.
All processing happens in your browser. Your text is never uploaded, stored, or shared, so the tool is safe for sensitive lists like contact details or internal data. It is completely free, with no account or sign-up required.