Remove Duplicate Lines cleans up lists in seconds. Remove repeated lines, remove empty lines, sort A to Z or Z to A, reverse the order, or trim extra spaces.
Clean up lists and text lines
Lists are everywhere: email addresses, keywords, product names, usernames, URLs and data copied from a spreadsheet. Lists often contain duplicates, empty lines or messy ordering. This tool cleans them in one step. You can remove duplicate lines, remove empty lines, sort A to Z or Z to A, reverse the order or trim extra spaces from every line.
What each action does
Remove duplicate lines. Keeps the first occurrence of each line and removes the repeats. You can decide whether upper and lower case letters count as different, so Apple and apple can be treated as the same or as two separate lines.
Remove empty lines. Deletes blank lines and lines that contain only spaces.
Sort A to Z and Z to A. Orders lines alphabetically in either direction using your language’s rules.
Reverse order. Flips the list, so the last line becomes the first.
Trim spaces. Removes spaces at the beginning and end of each line, which often fixes lists copied from tables or PDFs.
Real-life examples
- Email marketing. Remove duplicate addresses before sending a newsletter.
- SEO and content. Clean keyword lists collected from several sources.
- Developers. Deduplicate log entries, configuration values or lists of URLs.
- Students and researchers. Sort references alphabetically.
- Online stores. Tidy product codes and remove blank entries from supplier files.
How the tool works
The text is split into lines wherever there is a line break. The chosen action is applied to the list, and the result is joined back into text. The result box shows how many lines remain, and a copy button helps you paste the cleaned list elsewhere. All processing takes place in your browser, so even long private lists stay on your device.
Tips for accurate cleaning
- If your list has extra spaces, run Trim spaces first and then Remove duplicate lines. Otherwise lines that look equal may differ by a hidden space.
- Decide on case sensitivity before removing duplicates in lists such as names or codes.
- Keep a copy of the original list until you have verified the result.
- For sorted output, remember that numbers sort as text, so 10 may appear before 2. Add leading zeros if you need numeric order.
- Run actions one after another to combine them, for example remove empty lines and then sort.
Troubleshooting
Duplicates are still there. The lines may differ by spaces or capital letters. Trim spaces and turn case sensitivity off.
The order did not change. Check that you selected a sorting action.
The browser is slow. Very large lists with many thousands of lines need memory. Process them in smaller parts.
Free and private
Paste your list, choose an action and copy the result. There is no limit and no sign-up.
A real-world example
Asma collects 800 keyword ideas from three different tools for a new blog. Many repeat, some have extra spaces and a few lines are empty. She pastes everything into the tool, runs Trim spaces, then Remove empty lines, then Remove duplicate lines and finally Sort A to Z. The clean list has 520 unique keywords that she can group into topics.
Checklist before you copy the result
- You decided whether capital letters should count as different.
- You trimmed spaces before removing duplicates.
- You compared the line count before and after.
- You saved the original list.
Related tools
Word Counter measures text length, Case Converter standardises capitalisation, and JSON Formatter helps when your list comes from structured data.
More questions about this tool
Does the order of lines stay the same after removing duplicates?
Yes. The first occurrence of each line stays in its original position and later copies are removed.
Can I clean a list copied from a spreadsheet column?
Yes. Copy the column, paste it here, run the actions you need and paste the result back. Each cell becomes one line.
Can I sort numbers correctly?
Sorting works alphabetically, so 10 appears before 2. Add leading zeros, such as 02 and 10, if you need numeric order.
How to use Remove Duplicate Lines
- Paste your list with one item per line.
- Choose an action.
- Click "Process lines" and copy the result.
Frequently asked questions
Is the check case sensitive?
By default it is not. Switch the option to Yes if "Apple" and "apple" should count as different.
Is there a line limit?
There is no fixed limit, but very large lists depend on your device memory.
Is this tool really free?
Yes. All tools on this website are free to use, with no sign-up needed.
Are my files and data safe?
Yes. Everything is processed inside your own browser. Your files and text are not uploaded to our servers.
Does it work on mobile?
Yes. The tools work on modern phones, tablets and computers.