Email lists with the same address three times, keyword lists merged from two tools, inventory pasted from two spreadsheets — duplicate lines creep into every list that was assembled by hand. Paste the list here and this tool returns it with each line appearing exactly once, in your browser, with nothing uploaded.
Your control over “duplicate”
Whether two lines are “the same” depends on the job, so the judgement calls are switches, not assumptions. Trim spaces (on by default) treats “ apple ” and “apple” as one line — trailing spaces are the most common hidden cause of “duplicates that won't delete”. Ignore letter case treats “Apple” and “apple” as the same line; leave it off when case carries meaning, as in passwords or product codes. Keep first / keep last decides which copy's position survives; most people want the first. Sorting A→Z afterwards is the fastest way to eyeball a list for near-duplicates the tool cannot judge — “apple” vs “apples”, for instance.
Blank lines
Blank lines are removed by default because pasted lists collect them like lint. Untick “Remove blank lines” if the empty lines are meaningful spacers in your list — the first blank will be kept and the rest treated as duplicates of it.
Worked example
The sample list — apple, banana, apple, Cherry, banana, a blank line, date — has 7 lines. With the default options the cleaned list is apple, banana, Cherry, date: 4 unique lines, 3 removed. Tick “Ignore letter case” and capital-C Cherry would match a lowercase cherry elsewhere in the list too.
How to use this tool
- Paste your list into the top box — one item per line.
- Choose the options: trimming and blank-line removal are on by default.
- Watch the cleaned list update below; check the counts agree with your expectation.
- Copy the result or download it as a .txt file.
Cleaning lists that came from spreadsheets
If your list is one column of a spreadsheet, copy just that column and paste it here; copy the cleaned result back the same way. For duplicates across two different lists, paste list A then list B into the same box — the tool does not care where a line came from, so B's repeats of A disappear too (keep “First copy” to preserve A's order).