Duplicate Line Remover
Paste a list and instantly remove duplicate lines. Three removal modes, case-insensitive matching, sorting, and a detailed report showing exactly what was removed - all in your browser.
Remove Duplicates in 4 Steps
Paste your list, choose a removal mode, hit the button, and get a clean deduplicated list with a full audit report.
Duplicate Line Remover - Clean Any List Instantly
Duplicate lines waste space, cause errors in imports, and make data hard to read. Whether you are cleaning an email list, deduplicating keywords for an SEO campaign, or removing repeated entries from a log file, this Duplicate Line Remover handles it in seconds - with features no other online tool offers.
Most duplicate removers give you a cleaned list and nothing else. This tool also gives you a Removed Lines Report - a full audit showing exactly which lines were removed, their original line numbers, and how many times each appeared. You never have to wonder what changed.
This Tool vs. Basic Duplicate Removers
| Feature | Basic Tools | This Tool |
|---|---|---|
| Remove duplicates | ✓ Keep first only | ✓ Keep First, Keep Last, or Remove All |
| See what was removed | No | ✓ Full report with line numbers & counts |
| Duplicate rate % | No | ✓ Shows percentage of duplicates |
| Case-insensitive | Sometimes | ✓ Toggle on/off |
| Trim whitespace | Rare | ✓ Default ON |
| Remove empty lines | Sometimes | ✓ Toggle |
| Sort output | Some | ✓ A→Z or Z→A after dedup |
| Character limit | ~10K–50K | 200,000 characters |
Three Removal Modes Explained
Features of This Tool
How to Use (Step-by-Step)
Use Cases & Examples
FAQs – Duplicate Line Remover
"Keep First" keeps the first instance of each line and removes later duplicates. "Keep Last" keeps the final instance and removes earlier ones. "Remove All Duplicates" removes every line that appears more than once, keeping only lines that are truly unique (appeared exactly once).
The report shows every line that was removed, its original line number, and how many total times that line appeared. This lets you audit exactly what changed without comparing the before and after manually.
When enabled, the tool treats "Apple", "apple", and "APPLE" as the same line for comparison purposes. The original casing of the kept line is preserved in the output.
It strips leading and trailing spaces from each line before comparing. This catches cases where " hello" and "hello" look different due to hidden spaces but are actually the same content. It is enabled by default.
Yes. Enable Sort A→Z for ascending alphabetical order or Sort Z→A for descending. Sorting is applied after deduplication, so it only affects the final unique lines. The two sort options are mutually exclusive.
It shows what fraction of your lines were duplicates. For example, if you had 100 lines and 30 were removed, the duplicate rate is 30%. It gives you an instant sense of data quality.
The tool accepts up to 200,000 characters. There is no hard line limit - the constraint is character-based. The indicator below the input turns amber at 80% and red at 95%.
Completely. All processing runs in your browser using JavaScript. Your text is never sent to any server, stored, or tracked. Close the tab and everything is gone.
Yes - it is one of the most common use cases. Enable Case Insensitive mode since email addresses are not case-sensitive. The tool will treat "John@Email.com" and "john@email.com" as duplicates.
Yes, unless you enable sorting. Without sorting, lines appear in the output in the same order they appeared in the input (minus the removed duplicates).
Start Removing Duplicates
Paste your list, choose a mode, and get a clean result with a detailed report of exactly what was removed. Free, private, browser-based.
🧹 Remove Duplicates Now