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Remove Duplicate Lines

Remove Duplicate Lines deletes repeated lines from a list and keeps only the first occurrence of each. It can also remove empty lines, trim whitespace around each line, ignore case differences, and either keep the original order or sort A→Z or Z→A (numbers sort naturally).

  • Free
  • No sign-up
  • Runs in your browser
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Result
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How to use the Remove Duplicate Lines

  1. Paste your list on the left, one item per line.
  2. Choose a sort order and toggle "Ignore case", "Trim whitespace" and "Remove empty lines".
  3. The deduplicated list appears instantly, and the status bar shows how many lines were removed.
  4. Press "Copy" or "Download".

Examples

Clean an email list

With "Ignore case" on, Amy@ and amy@ are treated as duplicates.

Input
amy@example.com
bob@example.com
Amy@example.com

bob@example.com
Output
amy@example.com
bob@example.com

Specs & key facts

KeepsThe first occurrence of each line
OptionsIgnore case, trim whitespace, remove empty lines
SortingOriginal order, A→Z, Z→A (natural: 10 after 9)
VolumeHandles 100,000+ lines instantly
ProcessingIn your browser (nothing is uploaded)
PriceFree, no sign-up

FAQ

Does removing duplicates change the order?

Not with "Original order" — each item stays where it first appeared. Order only changes if you choose a sort.

Can I use data from Excel?

Yes. Copy a column in Excel and paste it; each cell becomes a line.

Two lines look identical but were not removed. Why?

They probably differ by spaces or invisible characters. Turn on "Trim whitespace".