UlvixorDuplicate Line Remover
Remove repeated lines from a list or text while always keeping the first occurrence and the original order of the remaining lines. Perfect for cleaning up email lists, names, or records without shuffling them.
How it works
- Paste the text or list, one item per line.
- The tool goes through the lines in order and keeps only the first occurrence of each one.
- Enable 'Case-sensitive' if you want 'Email@mail.com' and 'email@mail.com' to be treated as different lines.
- Check how many duplicate lines were removed, then copy or download the result.
Use cases
- Clean up an email list before importing it into a bulk-sending tool.
- Remove repeated rows from data exported as plain text from a spreadsheet.
- Clean up a to-do list, set of keywords, or tags that has accumulated duplicates over time.
- Merge lists from multiple sources without losing the order in which items appeared.
Use cases
- Clean up an email list before importing it into a bulk-sending tool.
- Remove repeated rows from data exported as plain text from a spreadsheet.
- Clean up a to-do list, set of keywords, or tags that has accumulated duplicates over time.
- Merge lists from multiple sources without losing the order in which items appeared.
Common mistakes
- Using 'Sort Text Lines' with the duplicate-removal option when you actually need to preserve the text's original order.This tool doesn't reorder anything — it only removes repeats while keeping the lines in their original order.
- Not realizing that two lines with different trailing spaces (for example, an invisible stray space) aren't treated as duplicates.The comparison is exact, character by character, aside from the case-sensitivity option. If you suspect hidden spaces, run the text through 'Remove Extra Spaces and Blank Lines' first.
- Leaving 'Case-sensitive' off and expecting 'Email@mail.com' and 'email@mail.com' to be treated as separate records.By default the comparison ignores case; enable that option if you need them treated as different lines.
Frequently asked questions
This tool preserves the original order of the text and only removes repeats. 'Sort Text Lines' reorders the content (alphabetically, numerically, or by length) and, optionally, also removes duplicates as part of the sorting process.
The first occurrence of each line is always kept, in the order it appears in the original text, and later repeats are discarded.
Yes, the comparison is exact, character by character (aside from the case-sensitivity option). If two lines look identical but have different trailing spaces, they'll be considered different. You can first use 'Remove Extra Spaces and Blank Lines' to normalize the text.
No. Duplicate detection and removal happen entirely in your browser, without sending your data to any external server.
Alternatives
In the terminal, sort file.txt | uniq removes duplicates, but it also reorders the lines, which isn't always desirable. This tool removes duplicates without touching the original order, handy for cleaning up a pasted list without going through the terminal.