Remove Duplicate Lines

How to use it

Removing duplicate lines means scanning a list line by line and keeping only the lines that are unique, dropping any line that has already appeared earlier in the list. Instead of manually scrolling through a spreadsheet export or a pasted block of text hunting for repeats, the tool compares every line against the ones before it and strips out the copies automatically. This is useful any time you end up with a list that has accidental repeats: deduplicating an email or mailing address list before a campaign, cleaning up data exported from a CRM or spreadsheet that merged several files together, removing repeated log entries from a server log so you can see which errors actually happened and how many distinct ones there were, or tidying a keyword list scraped from several sources so the same keyword is not counted twice. The tool keeps the first occurrence of each line by default — the earliest copy in your pasted text survives and every later repeat of that exact line is removed, so the order of your original list is preserved. Turn on case-insensitive matching if your list mixes capitalization, so 'Apple' and 'apple' are treated as the same line and only one of them is kept. Turn on trim whitespace so a line with a trailing space or extra indentation is not mistaken for a different line just because of invisible characters. Turn on sort alphabetically if you want the final unique list ordered A to Z instead of in its original order. As a worked example, paste a short list: apple, banana, apple, cherry, banana, date. Without any options the tool keeps the first occurrence of each line and reports 4 unique lines kept and 2 duplicates removed, leaving apple, banana, cherry, date in that original order. If two of those lines only differed by capitalization or a trailing space, turning on case-insensitive matching or trimming would catch those extra duplicates too. To use it, paste your list into the input box, choose whichever options match your data, and the deduplicated result appears instantly in the output box, ready to copy with one click. For the cleanest results with real-world data, combine trim with case-insensitive matching: exported lists frequently contain the same value repeated with different capitalization or a stray trailing space, and both options together catch those near-duplicates that an exact match would miss.

Frequently asked questions

Which duplicate is kept?

By default the first occurrence of each line is kept and later duplicates are removed. Enable 'Sort alphabetically' to reorder the unique lines instead.

Does it ignore case and whitespace?

Optionally. 'Case-insensitive' treats 'Apple' and 'apple' as the same, and 'Trim each line' ignores leading and trailing spaces when comparing.

Is my text sent to a server?

No. Everything runs in your browser — your text is never uploaded.

Will it change the order of my lines?

No, not unless you turn on sorting. By default the tool keeps every unique line in the same order it first appeared in your original list, only removing the later repeats. Enable 'Sort alphabetically' if you want the unique lines reordered A to Z instead of preserving their original position.