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Paste any list and strip out the repeated lines in one click — with options to sort A–Z, ignore letter case, trim stray spaces and drop blank lines. Mailing lists, keyword lists, inventories, invite lists: if it's one item per line, this cleans it.
Duplicates creep into every list that more than one person — or one person, twice — has touched. Two exports merged. Sign-ups collected from a form and a spreadsheet. Keywords gathered from three tools. Products typed by hand over months. The result is a list where “Acme Corp”, “acme corp” and “Acme Corp ” (with a trailing space, invisible and infuriating) are three separate lines, and any system importing the list treats them as three different entries. Finding duplicates by eye works for twenty lines. For two thousand, it's this tool.
Paste the list, choose your rules, click once. Sort A→Z gives you a tidy alphabetical result. Ignore case treats “Apple” and “apple” as the same entry. Trim spaces removes leading and trailing whitespace — the silent cause of most “but I deleted that duplicate!” arguments. Remove blank lines clears the gaps. The counters show lines before, unique lines after, and exactly how many duplicates were removed, so you can verify the cleanup before you trust it — all processed in your browser, so even a customer list never leaves your machine.
A small shop merges two staff-collected lists of customer phone numbers for a WhatsApp broadcast: 1,240 lines total. With trim spaces and blank lines removed, the tool reports 861 unique lines and 379 duplicates removed — nearly a third of the list was repeats, including the same number pasted by both staff members and a few numbers with spaces copied from the contacts app.
The payoff isn't just tidiness. Sending the broadcast from the cleaned list means no customer gets the same promotional message three times in a minute — the kind of thing that gets a number blocked. And when the shop's owner glanced through the sorted output, two numbers with transposed digits stood out as obvious typos. Sorted, deduped lists are simply easier to trust.
It compares lines exactly as written — after applying the options you chose. With Trim spaces on, “ apple ” becomes “apple” before comparing. With Ignore case on, “Apple” and “apple” compare as equal. The first occurrence is kept (or its position in the sorted output), and later repeats are removed.
Either way you get the same unique set — sorting is about how the output is presented. Sorted output is easier to scan for near-duplicates and typos, which is why most people leave it on.
Yes. Because processing happens in your browser, lists of hundreds of thousands of lines are handled in moments on a typical computer. There's no upload, so the list can be as private as you need.
If you tick “Remove blank lines”, yes — empty lines and lines containing only spaces are dropped from the output. Leave it unticked if blank lines are meaningful separators in your data.
No. The list is processed locally in your browser and disappears when you close the tab — safe for customer data, email lists and anything else you'd never paste into a server-side tool.
Run the tool on a copy of your list and compare the counters: “Lines before” minus “Unique lines” tells you exactly how many repeats exist, and sorting both versions side by side shows you where they cluster — then dedupe the real list when you're ready.