Duplicate Line Remover
Paste a list and this tool removes the repeated lines, keeping your entries in their original order. You can also strip blank lines, keep only the lines that appear once, or flip it around and see just the duplicates.
About this Duplicate Line Remover
This tool cleans up a list by finding lines that appear more than once and removing the extra copies. Paste your list into the box, one entry per line, and click Remove Duplicates. The result keeps your entries in their original order rather than sorting them, so a list of names, emails, or URLs comes back looking the same — just without the repeats. The counters show how many lines went in, how many were kept, how many were removed, and how many distinct entries were repeated.
The What to keep menu covers four jobs. The first two remove duplicates and differ only in which copy survives: the first occurrence or the last. Keep only lines that appear exactly once is stricter — if an entry appears twice, every copy is dropped, which is how you isolate the genuinely unique items. Show only the duplicated lines inverts the tool and lists one copy of each entry that appeared two or more times, which is the quickest way to audit what was repeated before you delete anything.
The options control what counts as "the same line". Ignore surrounding spaces is on by default because a trailing space is invisible and would otherwise make two identical entries look different. Ignore letter case treats Alice@example.com and alice@example.com as one entry, which matters for email and username lists. Remove blank lines clears out empty rows left behind by copying and pasting, and Trim spaces in the result tidies the output itself rather than only the comparison. Changing any option re-runs the clean-up straight away.
Typical uses include tidying mailing lists and contact exports, deduplicating URLs or keyword lists before an import, cleaning log files, merging two lists that overlap, and checking a spreadsheet column for accidental repeats. When duplicates are found, a small table shows the most repeated entries with their counts, so you can see at a glance whether one line was pasted twice or fifty times. Use Copy Result or Download .txt to take the clean list away, or Use as Input to feed it back in and run another pass with different options.
Note: Everything runs inside your browser and nothing is uploaded, so it is safe to paste private lists. Lines are compared as whole lines — entries separated by commas on a single line are not split up, so put one item per line first if your data is comma separated.