Remove Duplicate Lines
Instantly deduplicate text — sort, trim, and clean in one click
9
Input Lines
5
Unique Lines
4
Removed
Input
Unique Lines
About the Duplicate Line Remover
This tool removes duplicate lines from text, keeping the first occurrence of each so the original order survives. Optional whitespace trimming and case-insensitive matching catch the near-duplicates that differ only by a stray space or a capital letter, which exact matching would miss.
Remove duplicate lines whenever lists get combined. Merged email exports, keyword research from several tools, log files concatenated together, or a URL list assembled from multiple crawls all end up with repeats.
The options exist because exact matching misses most real duplicates. " [email protected]" and "[email protected]" differ by one space; "[email protected]" differs by case. Trimming whitespace and ignoring case first is usually what you actually want.
The first occurrence of each line is kept so the original order survives, and sorting alphabetically afterwards is optional. Empty lines can be dropped in the same pass. Everything runs in your browser, which matters for email lists and customer data.
How to use the Duplicate Line Remover
- Paste your list. Enter the lines you want deduplicated.
- Set the matching options. Turn on trimming and case-insensitive matching to catch near-duplicates.
- Remove duplicates. The first occurrence of each line is kept.
- Sort and copy. Optionally sort alphabetically, then copy the clean list.
Duplicate Line Remover features
- Keeps the first occurrence, so the original order survives
- Optional whitespace trimming before comparison
- Case-sensitive or case-insensitive matching
- Optionally drop empty lines
- Optionally sort the result A to Z
- Input, unique and removed line counts reported
- Copy the result
Frequently asked questions
Which duplicate is kept?
The first one. Later copies are removed, so the order of what remains matches the order you supplied — which matters when the list is ranked or chronological.
Why would identical-looking lines not match?
Usually a trailing space, or a capital letter. Turn on whitespace trimming and case-insensitive matching to catch those; exact matching treats them as different lines, which is correct but rarely what you want.
What are the counts for?
A sanity check. If you paste 5,000 lines and 4,000 come back as duplicates, something upstream is repeating itself and that is worth knowing before you use the result.
Can it sort the output too?
Yes, there is an option to sort alphabetically after deduplicating. Leave it off when the existing order carries meaning.