Free Duplicate Line Remover
Remove duplicate lines from any list instantly. Paste your text, get unique lines with one click. Supports case-insensitive matching, sorting, and whitespace trimming. Free, no signup, works entirely in your browser.
How to Remove Duplicate Lines Online
1. Paste your list into the input box above with one item per line. The tool works with any text: email addresses, names, URLs, product SKUs, keywords, or any other list.
2. Configure options. Choose whether to trim whitespace, remove empty lines, use case-sensitive matching, and how to sort the output. The defaults handle most use cases automatically.
3. Copy the unique lines with one click. The output shows only the first occurrence of each line with all duplicates removed.
When to Use a Duplicate Remover
Email lists: Clean up mailing lists by removing duplicate email addresses before importing into Mailchimp, SendGrid, or any email marketing platform. Prevents sending duplicate messages.
Spreadsheet data: Copy a column from Excel or Google Sheets, paste it here to remove duplicates, then paste the clean list back. Faster than spreadsheet formulas for quick deduplication.
SEO keyword lists: Merge keyword lists from multiple tools (Ahrefs, SEMrush, Google Keyword Planner) and remove duplicates to get a clean, unique keyword list.
Log files: Paste server logs, error messages, or IP addresses to find unique entries and identify the most common duplicates.
Code cleanup: Remove duplicate imports, CSS classes, configuration entries, or any repeated lines from source code files.
Survey responses: Deduplicate free-text survey responses to identify unique answers and count their frequency.
Features
By default, 'Apple' and 'apple' are treated as duplicates. Enable case-sensitive mode when capitalization matters.
Automatically trims spaces and tabs from the beginning and end of each line before comparing. Catches duplicates that differ only by whitespace.
Removes blank lines and lines containing only whitespace. Keep them by toggling the option off.
Keep original order, or sort alphabetically A-Z or Z-A. Sorting makes it easy to scan the list visually.
See how many total lines, unique lines, and duplicates were found. The 'Most Duplicated' section shows which lines appeared most often.
Click 'Apply to Input' to replace your original text with the deduplicated result. Useful for running additional cleaning passes.
Frequently Asked Questions
How does this duplicate line remover work?
Paste your list with one item per line. The tool compares each line and keeps only the first occurrence of each unique line. Duplicates are removed instantly. You can choose case-sensitive or case-insensitive matching, trim whitespace, remove empty lines, and sort the results.
Is the comparison case-sensitive?
By default, no. 'Apple' and 'apple' are treated as the same line and the duplicate is removed. Enable the 'Case sensitive' option if you need to keep lines that differ only in capitalization.
Does this tool preserve the original order?
Yes, by default. Lines appear in the same order as the input, with duplicates removed. You can also sort the results alphabetically (A to Z or Z to A) using the sort options.
What happens to blank lines?
By default, blank lines and lines containing only whitespace are removed. Disable the 'Remove empty lines' option if you want to keep them.
Can I see which lines were duplicated the most?
Yes. The 'Most Duplicated' section below the options shows the top 5 most frequently repeated lines and how many times each appeared in the original input.
Is there a line limit?
No hard limit. The tool processes text entirely in your browser, so it can handle thousands of lines. Very large lists (100,000+ lines) may be slow depending on your device.
Can I use this to deduplicate email lists?
Yes. Paste your email addresses one per line and the tool will remove duplicates. Enable 'Case sensitive' off (the default) since email addresses are case-insensitive. Enable 'Trim whitespace' to handle extra spaces.
Is my data sent to a server?
No. All processing happens in your browser using JavaScript. Your text never leaves your device.
More Free Text Tools
Deduplicate your list here, then use our other tools to convert case, count words, clean up formatting, or generate placeholder text.