Paste your list and remove duplicate lines instantly — sort, deduplicate, and copy in one click.
🔒 Runs in your browser — your text never leaves this pageA duplicate line remover is a text utility that scans a list — one item per line — and keeps only unique entries, discarding every repeated occurrence. It sounds simple, but the problem of duplicate lines is surprisingly common. Any time you merge data from multiple sources, export a report, or compile a list from copy-pasted content, duplicates creep in without you noticing.
Duplicate lines appear in many real-world scenarios: combining keyword lists from different research tools, exporting raw CSV data from a CRM, pulling product tags from multiple categories, or aggregating error logs from a server. In every case the result is a bloated, hard-to-read list where repeated lines add noise and can cause downstream errors — especially when the list is imported into another tool.
This online duplicate line remover lets you paste any plain-text list and get clean, unique lines back in an instant. Unlike Excel's "Remove Duplicates" feature — which requires your data to be in a spreadsheet column — this tool works directly with plain text. No columns, no formatting, no software required. Your text never leaves your browser — everything is processed locally using JavaScript, so your data stays completely private.
| Input (with duplicates) | Output (unique lines) | Lines removed |
|---|---|---|
| [email protected] [email protected] [email protected] [email protected] [email protected] |
[email protected] [email protected] [email protected] |
2 duplicates removed |
| running shoes best running shoes running shoes trail running shoes best running shoes |
running shoes best running shoes trail running shoes |
2 duplicates removed |
| Germany France Germany Italy France Spain |
Germany France Italy Spain |
2 duplicates removed |
| error: connection timeout error: 404 not found error: connection timeout error: connection timeout error: 500 internal |
error: connection timeout error: 404 not found error: 500 internal |
2 duplicates removed |
Paste your list into the Input box above — one item per line. Duplicate lines are removed automatically as you type. Use the options to control case sensitivity and whitespace handling, then click "Copy result" to use the cleaned list.
By default, two lines are duplicates when they are character-for-character identical, including capitalization and spacing. Enable "Case-insensitive" to treat "Apple" and "apple" as duplicates, or "Trim whitespace" to ignore leading and trailing spaces before comparing.
Standard mode is case-sensitive — "Apple" and "apple" are treated as different lines and both kept. Check "Case-insensitive" to make the comparison ignore case, keeping only the first occurrence regardless of how it is capitalized.
If your CSV has one value per row (or you need to deduplicate a single column), copy that column of values and paste it here. Each row becomes a line, and duplicates are removed instantly. For multi-column CSVs, use a spreadsheet tool like Google Sheets or Excel instead.
Excel's Remove Duplicates operates on spreadsheet cells and columns — your data must be in a formatted table. This tool works with raw plain text: paste any list, get unique lines back, no spreadsheet needed. It's faster for quick deduplication tasks and works on any device with a browser.
There is no hard limit enforced by the tool. In practice, lists of tens of thousands of lines process in milliseconds. For very large files (hundreds of thousands of lines), performance depends on your device's available memory. For files that size, a command-line tool like sort -u on Linux may be more practical.
Your text never leaves your browser — everything is processed locally using JavaScript running on your device. Nothing is transmitted to any server, stored, or logged. You can even use this tool offline once the page has loaded.