Remove Duplicate Lines & Sort Lines

What the tool does

Lists collect duplicates: email addresses from several sources, keywords, log lines, product codes. This tool removes repeated lines and keeps the first copy of each one, with options to ignore case, trim spaces and drop empty lines. You can also sort the result or show only the lines that were repeated. It runs in your browser, so your list is not uploaded.

How to use it

• Paste your list, one item per line.
• Choose whether matching is case sensitive, whether to trim spaces and whether to remove empty lines.
• Choose an order: keep the original order, sort A to Z or Z to A, numerically, by length, or reverse.
• Switch to repeated lines only if you want to see what was duplicated.
• Copy the result. The counters show input lines, unique lines and duplicates removed.

Example

Case-insensitive matching with trimmed spaces:

Input        Output (case insensitive, trimmed)
apple        apple
banana       banana
Apple        cherry
cherry       date
banana
  cherry
date

Tips

• Turn on trim first. Trailing spaces are the most common reason that two identical-looking lines are not matched.
• Case sensitive matching treats Apple and apple as different lines. Turn it off to treat them as the same.
• Use numeric sort for lists of numbers so 10 comes after 9, not after 1.
• To find what is repeated rather than remove it, use the repeated lines only view.

Real examples

Where a duplicate remover saves time:

• Cleaning an email list collected from several forms before you import it.
• Merging keyword lists from different research tools.
• Finding repeated entries in a log file or an export.
• Making a list of unique product codes, domains or usernames.

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