Remove Duplicate Lines
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Clean duplicate entries out of any list — emails, URLs, keywords, log lines. The first occurrence of each line is kept and the rest are removed.
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How to use this tool
- Paste your list, one entry per line.
- Choose case-sensitive or insensitive matching, and whether to trim spaces.
- Click Remove duplicates.
- Copy the cleaned list — the summary shows how many lines were removed.
About this tool
Merged mailing lists, exported keyword sets and concatenated logs accumulate duplicates that are tedious to remove by hand. Paste the list and the tool keeps the first occurrence of each line, preserving your original order. Case-insensitive matching treats "Apple" and "apple" as the same entry; optional whitespace trimming catches lines that differ only by stray spaces. The result reports exactly how many duplicates were removed.
Frequently asked questions
- Which copy of a duplicate is kept?
- The first one, in its original position — the rest are removed, so your list order is preserved.
- Are "Item" and "item " treated as duplicates?
- Only if you enable the matching options: case-insensitive matching equates the capitalization, and trimming ignores leading/trailing spaces. Both are optional so you stay in control.
- Can I deduplicate and sort at the same time?
- Deduplicate here first, then paste the result into the Sort Lines tool — keeping the steps separate makes each result easy to verify.
Related tools
Sort LinesPut any list in order: alphabetical (A–Z or Z–A), natural numeric order, or by line length — with one click.Remove Extra SpacesClean up messy whitespace: collapse repeated spaces, trim the ends of lines, and remove empty lines — each cleanup individually selectable.Find & ReplaceReplace every occurrence of a word or phrase in pasted text. Supports case-sensitive matching, whole words only, and regular expressions.