Remove Duplicate Lines
Filter duplicate rows from text lists or database exports. Includes case-sensitive matching and whitespace trimming.
Your text 57 chars · 9 lines
Result 5 unique · 4 of 9 lines removed
How to use Remove Duplicate Lines
- Paste list lines into the input area.
- Configure options such as case sensitivity or whitespace trimming.
- Copy or export the unique lines.
About Remove Duplicate Lines
Remove repeated lines from a list and keep only the first time each line appears. Paste emails, keywords, product codes, or any line-based list, and the unique result appears instantly, along with how many lines were removed.
Related tools: Word Counter, Byte Counter & Character Counter, Case Converter — Title Case & More, Remove Extra Spaces
How duplicates are matched
Two lines count as duplicates when their text matches. By default the match ignores capitalization, so Apple and apple are treated as the same line, and spaces at the start or end of a line are ignored. Turn on Case-sensitive to keep Apple and apple as separate lines.
The first occurrence of each line is kept in its original position, and later copies are removed. The tool does not sort the list, so the order you pasted is preserved. If you also want the list alphabetized, run the result through the Sort Lines tool.
Blank lines and spacing
Remove blank lines drops empty lines entirely, which is usually what you want when cleaning a list. Turn it off if blank lines separate groups you need to keep.
Ignore spaces at line edges also trims those spaces in the output, so the cleaned list is ready to paste into a spreadsheet, form, or code without stray whitespace.
Common uses
- Email lists
- Remove repeated addresses before importing a mailing list, ignoring differences in capitalization.
- Keyword research
- Combine keyword exports from several tools and keep one copy of each phrase.
- Inventory and SKUs
- Find out how many unique product codes are in a pasted column.
- Log lines
- Collapse repeated log or error messages to see each distinct one once.
Questions about Remove Duplicate Lines
- Does deduplication preserve line order?
- Yes. The first occurrence of each unique line remains in its original position.
- Can I treat "Apple" and "apple" as different?
- Yes. Turn on Case-sensitive and lines that differ only in capitalization are kept.
- How do I see how many duplicates there were?
- The summary above the result shows the number of unique lines and how many of the original lines were removed.
- Can I remove duplicates from a spreadsheet column?
- Yes. Copy the column, paste it here, remove duplicates, and paste the result back. Each cell becomes one line.
- Is there a limit on how many lines I can paste?
- No fixed limit. Lists of tens of thousands of lines are processed instantly.
More tools like Remove Duplicate Lines
- Word CounterCount words, characters, sentences, paragraphs, and reading time.
- Byte & Character CounterCount UTF-8 bytes, characters, letters, digits, and whitespace.
- Case ConverterConvert text to uppercase, lowercase, title case, camelCase, snake_case, and kebab-case.
- Remove Extra SpacesStrip duplicate spaces, tabs, empty lines, and trailing whitespace.
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