Remove Duplicate Lines
Remove Duplicate Lines strips repeated lines from any list, keeping the first time each line appears and preserving the original order. Optional toggles let you ignore case, trim surrounding whitespace before comparing, and drop empty lines.
It all happens in your browser, so even large lists of emails, URLs or keywords stay private.
How to use Remove Duplicate Lines
- 1
Paste your list
Drop in any text where each item is on its own line.
- 2
Choose your matching options
Optionally ignore case, trim whitespace, or remove empty lines before deduplicating, and choose whether to keep the first or last occurrence.
- 3
Copy the unique lines
The cleaned list with input, kept and removed counts appears instantly — optionally sort it A→Z, then copy or download the result.
Keep the first or last occurrence
By default the first appearance of each line is preserved and later copies are removed, so the original ordering is maintained — safe for ranked lists, configuration files and ordered data. Switch to “keep last” when the most recent entry is the one that matters, such as deduplicated log lines.
Enable “Sort result” to alphabetize the unique lines in the same pass, no second tool needed.
Case and whitespace matching
By default, comparison is exact. Turn on "ignore case" so that "Apple" and "apple" are treated as the same line. Turn on "trim whitespace" so that lines differing only by leading or trailing spaces are also collapsed together.
These options matter when deduplicating data pasted from spreadsheets or scraped from the web, where invisible inconsistencies are common.
Frequently asked questions
- Does it keep the original order?
- Yes, unless you sort. By default the first occurrence of each line stays in place and the order of the remaining lines is unchanged. You can switch to keeping the last occurrence, or enable “Sort result” to alphabetize the output.
- Can it ignore case when comparing?
- Yes. Enable "ignore case" to treat lines that differ only in capitalization as duplicates.
- Is my data uploaded?
- No. Deduplication runs entirely in your browser.
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