Keyword lists, email lists, scraped data, log files — pasted lists almost always contain repeats, and cleaning them by hand is miserable. Our free Remove Duplicate Lines tool does it in one click: paste your list, and it keeps only the first occurrence of each unique line. No signup, no upload, and your data never leaves your browser.
You control exactly what counts as a duplicate. Case-sensitive mode (on by default) treats “Apple” and “apple” as different lines; turn it off to merge them. Trim-whitespace removes stray spaces before comparing, which catches duplicates that only differ by invisible padding. An optional A-to-Z sort tidies the output in the same step.
SEO specialists cleaning keyword exports, data analysts deduplicating rows, and anyone preparing mailing or survey lists will find it a daily time-saver. A stats line tells you exactly how many duplicates were removed and how many unique lines remain, so you always know what changed.
Remove Duplicate Lines
Paste a list and keep only the first occurrence of each line.
How to use
- Paste your list into the text box, one item per line.
- Keep “Case sensitive” ticked if “Apple” and “apple” should count as different; untick it to merge them.
- Keep “Trim whitespace from lines” ticked to catch duplicates that differ only by extra spaces.
- Tick “Sort result A to Z” if you also want the output alphabetized.
- Click “Remove duplicates” and read the stats line (“Removed N duplicates — M unique lines remain”).
- Copy the result or download it as a .txt file.
FAQs
Which occurrence is kept when a line repeats?
The first occurrence. The tool preserves the original order of first appearances (unless you enable sorting), so your list’s natural sequence is kept intact.
Why would I trim lines before comparing?
Lists copied from spreadsheets and exports often carry trailing spaces, making “apple” and “apple ” look identical but technically different. Trimming treats them as the same line so the duplicate is actually removed.
Is there a limit on how many lines I can process?
No server-side limit exists because everything runs in your browser. Extremely large lists (hundreds of thousands of lines) may take a moment, but typical lists of thousands of lines are instant.