Remove Duplicate Lines
Paste a list, remove every repeated line, and keep the first occurrence in its original order.
How to use the remove duplicate lines
- Paste your list or text, one item per line.
- Choose whether to ignore spacing and/or letter case when comparing lines.
- Click “Remove duplicate lines”, then copy or download the cleaned-up result.
Features
- Keeps the first occurrence and original line order
- Optional case-insensitive and whitespace-insensitive matching
- Copy to clipboard or download as a .txt file
How duplicate line removal works
This tool is useful for cleaning copied lists, keyword sets, IDs, email exports and other line-based text while preserving the first occurrence. It is especially handy before sorting or comparing two lists.
Small differences can make two lines technically different. Leading spaces, punctuation or capitalization may prevent a match depending on how the source text is written, so normalise the text first if you need case-insensitive or whitespace-insensitive deduplication.
For very large lists, decide whether blank lines should count as values before deduplicating. Cleaning whitespace first can produce a more predictable result when data has been copied from spreadsheets, logs or exported systems.
Frequently asked questions
Related tools
Decide what “duplicate” means for your data
Two lines can look the same to a person but differ because of spaces, capitalisation or hidden characters. Clean the text consistently before deduplicating if those differences should not create separate entries.
- Decide whether case differences such as “Apple” and “apple” should count separately.
- Trim unwanted leading and trailing spaces first when data comes from spreadsheets.
- Keep an original copy when deduplicating a list that cannot be reconstructed easily.
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