Remove Duplicate Lines
Online duplicate line remover. Find and delete duplicate lines from your text. Options for case sensitivity and whitespace handling.
Why remove duplicate lines online?
Duplicate data is a common problem when merging lists, analyzing logs, or collecting user inputs. Cleaning these up manually is impossible for large datasets. A duplicate line remover is essential for ensuring data integrity. Our Remove Duplicates Tool finds and eliminates repeated lines from your text instantly. It keeps the first instance of a unique line and deletes subsequent copies. You can use it to clean email lists, dedup database queries, or simply tidy up your notes. With efficient client-side logic, it can handle thousands of lines in seconds without compromising privacy.
Efficient Deduplication
Instant Cleanup
Paste thousands of lines and get a clean, unique list instantly. The tool highlights how many duplicates were found and removed.
Case Sensitivity Control
Choose whether to treat 'Text' and 'text' as the same line or different lines. giving you full control over the filtering logic.
Whitespace Handling
Smart trimming ensures that lines with trailing spaces aren't treated as unique duplicates. We clean the noise so you get accurate results.
Privacy & Security
Your data lists never leave your computer. Deduplication is performed locally, making it safe for business-critical data.
Frequently Asked Questions
Does this tool delete the original line?
No, it keeps exactly one copy of every unique line found. Only the extra copies (the 2nd, 3rd occurrence, etc.) are removed.
Can I check for duplicates without deleting them?
Currently, the tool automatically produces the cleaned output. You can compare the 'Original Line Count' vs 'New Line Count' to see if duplicates existed.
Does it ignore case?
We provide a toggle for Case Sensitivity. If disabled (default), 'Hello' and 'hello' are seen as duplicates. If enabled, they are kept as unique lines.
Is there a limit on file size?
The tool works best with text up to a few megabytes (approx 100,000 lines). Very large files may be limited by your browser's memory.