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Remove Duplicate Lines

Delete repeated lines from a list, keeping the first of each.

2 duplicate lines removed
Original lines6
Unique lines4
apple
banana
cherry
date

Paste a list to remove duplicate lines and keep only the unique ones (in their original order). Handy for cleaning up email lists, keywords, logs and any line-based data.

Formula / method

keep the first occurrence of each line, drop later repeats

Examples

apple, banana, apple
apple, banana
5 lines, 2 repeats
3 unique lines

Keeping one of each

Paste a list and this tool walks through it from top to bottom, keeping the first time each line appears and dropping every later copy. The original order of the surviving lines is preserved, so it is not the same as sorting; it simply removes repetition. This is ideal for cleaning up email lists, tag collections, log entries or any list that has accumulated duplicates.

The whole operation happens in your browser, so even large pastes stay private and process instantly.

What counts as a duplicate

Two lines match only if they are identical, and small differences can hide that they are meant to be the same. Trailing spaces, a stray tab, or a difference in capitalisation such as Apple versus apple will normally be treated as distinct lines. If you want a cleaner result, trim and lowercase your list first. To reorder the deduplicated output alphabetically afterwards, run it through the Sort Text Lines tool, which pairs naturally with this one.

Where it's used

  • Cleaning a list of email addresses or usernames before an import
  • De-duplicating URLs collected from several crawls or bookmark exports
  • Removing repeated entries from a CSV column pasted as lines
  • Tidying an SEO keyword list so each term appears only once
  • Merging two lists and stripping the overlap

Real-world examples

  • A marketer pastes 500 exported email addresses and removes about 40 duplicates before uploading to a mailing tool.
  • A list of collected domains has the same site several times; deduping leaves one of each.
  • Two merged to-do lists collapse into a single clean set of unique tasks.

Did you know?

The classic Unix uniq command only collapses duplicate lines that sit next to each other, which is why it's almost always run after sort; a whole-list deduper like this one finds repeats no matter where they appear.

FAQ

Does it change the order?

No — it keeps lines in their original order and simply removes later duplicates. Matching is exact (case- and space-sensitive).

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