Remove duplicate items from a list
Paste a list and get a clean one back, with the repeated items removed. Ignore case and surrounding spaces if you want “dune” and “Dune ” treated as one, and the page reports how many rows were duplicates before it drops them.
Nothing is uploaded and nothing is saved. These tools read what you paste and do the work in your own browser. No data is sent to this server, stored in a cookie, or kept after you close the tab.
About duplicates
Which copy is kept?
The first one. Every later repeat is removed, so the order of first appearances is preserved unless you ask for sorting.
Does it tell me what was removed?
Yes — the duplicates are listed separately under the clean list, with a count, so you can see what left the list rather than trusting that nothing did.
Is “ISBN” the same as “isbn”?
Yes when “Ignore case” is on, which is the default. Turn it off to match exactly, case and all.