How to use the Duplicate Line Remover
- 1
Paste your list with one item per line.
- 2
Choose options such as “Ignore case”, “Trim whitespace” or “Sort result”.
- 3
Review how many duplicates were removed.
- 4
Copy or download the clean list.
Features & benefits
Keeps the first occurrence
Original order is preserved unless you choose to sort.
Flexible matching
Treat “Apple” and “apple ” as the same item with case and whitespace options.
Sorting built in
Sort alphabetically A–Z or Z–A, with natural number ordering.
Handles big lists
Deduplicates 100,000+ lines instantly using an efficient hash set.
Cleaning lists the right way
Duplicate entries cause double-sent emails, inflated keyword counts and skewed reports. Removing them is usually the first step in tidying any exported list.
Real-world data is rarely consistent: the same email might appear once in capitals and once with a trailing space. Turning on “Ignore case” and “Trim whitespace” catches these near-duplicates while still outputting the first version exactly as it was written.
Frequently asked questions
Which copy of a duplicate is kept?
The first occurrence is kept and later repeats are removed, so the original order of your list is preserved.
Are empty lines removed?
Only if you tick “Remove empty lines”. Otherwise, repeated blank lines are treated like any other duplicate.
Can I use it for CSV files?
Yes. Each full row is compared as one line, so identical rows are removed. Paste the CSV contents directly.