About the Remove Duplicate Lines
Tezmy's Remove Duplicate Lines tool cleans up any list in one step. Paste emails, names, keywords, product codes or URLs, one per line, and every repeated line is removed instantly while the first copy is kept in its original position. You can ignore capital letters and stray spaces so near-duplicates are caught too, drop empty lines, and sort the result from A to Z or Z to A. Numbers sort naturally, so item 2 comes before item 10.
Updated October 2026
How to use the Remove Duplicate Lines
- 1Paste your list, one item per line.
- 2Choose whether case and extra spaces matter.
- 3Pick a sort order, or keep the original order.
- 4Copy or download the cleaned list.
Common uses
- Cleaning email lists before sending a newsletter.
- Removing repeated keywords, hashtags or URLs.
- Tidying names, product codes or order numbers from spreadsheets.
- Merging two lists and removing the overlap.
Catch near-duplicates too
“Apple”, “apple” and “Apple ” with a trailing space look different to a computer. Turn on ignore case and ignore spaces to treat them as the same. The first version you typed is kept, so your preferred spelling stays.
Sort your list
Sort A to Z or Z to A after removing duplicates. Natural sorting puts “item 2” before “item 10”, the way people expect, instead of the computer order where 10 comes first. You can also just sort a list without anything else changing.
Paste from Excel or Google Sheets
Copy a single column and paste it here: each cell becomes one line. After cleaning, copy the result and paste it back into your spreadsheet. The count of removed lines shows how many duplicates you had.
Private list cleaning
Customer lists, emails and order numbers are personal data. This tool cleans them in your own browser, so nothing is uploaded or stored. Open this page in Safari, Chrome or Edge on your phone, tablet or computer. There's nothing to install and no sign-up, and everything runs on your own device, so what you type is never uploaded. After cleaning a list, count what is left with the Word Counter, and change the capitals with the Case Converter so that "Apple" and "apple" no longer look different. For web addresses and file names, the Slug Generator turns each line into a tidy URL-friendly version.
Features
- Removes duplicates instantly
- Case-insensitive option
- Ignores stray spaces
- Removes empty lines
- Natural A–Z and Z–A sorting
- Shows how many were removed
Frequently asked questions
Which copy of a duplicate is kept?
The first one. Later repeats are removed, so your list keeps its original order unless you choose to sort it.
Will “Apple” and “apple” count as duplicates?
Yes, by default. Tick “Case sensitive” if you want them treated as different lines.
Can I sort my list without removing duplicates?
This tool always removes duplicates. If your list has none, it simply sorts it.
How does natural sorting work?
Numbers inside lines are compared by value, so “file 2” comes before “file 10”, the way people expect.
Is there a size limit?
No fixed limit. Lists with hundreds of thousands of lines work fine on most devices.
How do I remove duplicate emails from a list?
Paste the emails one per line, turn on ignore case (email addresses aren't case-sensitive) and copy the cleaned list.
Does it work with thousands of lines?
Yes. Lists with tens of thousands of lines are cleaned in a moment, right on your device.
Is my list uploaded anywhere?
No. Everything happens in your browser, which matters for customer and email lists.
Does it keep the original order?
Yes, unless you choose to sort. Each line stays where its first copy was, and later repeats are removed.
Can I remove empty lines too?
Yes. Turn on the option to drop empty lines and the result has no blank gaps.
Is it free?
Yes. No sign-up and no limit on how many lists you clean.
Does it work on my phone?
Yes. Paste a list from any app, clean it and tap Copy to paste it back.