Remove Duplicate Lines

By default, no. The original order of the first occurrence of every line is perfectly preserved. However, you can optionally check "Sort Output" to alphabetically organize the unique lines.

Yes! Because this tool leverages native JavaScript Set data structures, it can process hundreds of thousands of lines in milliseconds right inside your browser.

Never. Your data remains completely private. All text processing occurs locally on your machine.

The tool checks for exact string matches on a line-by-line basis. If two lines have the exact same characters in the exact same order, the second occurrence is considered a duplicate and is removed.

It is likely due to whitespace or casing differences. For example, "Apple" and "apple" are technically different. You can enable "Case Insensitive" or "Trim Spaces" to catch these hidden duplicates.

Paste your list of emails into the text box. We highly recommend checking the "Case Insensitive" and "Trim Spaces" options, as emails are case-insensitive and often have accidental trailing spaces.

There is no hard limit imposed by the tool, but very large datasets (e.g., millions of lines) may cause your web browser to temporarily freeze or run out of memory while it calculates the duplicates.

Simply check the "Sort Output" box before or after pasting your text. It will instantly re-organize the remaining unique lines in alphabetical order.

The log is a helpful feature that shows you a breakdown of exactly which lines were deleted and how many times they appeared in your original text, allowing you to analyze patterns in your data.

Yes! The tool is completely responsive and works on smartphones and tablets. Just copy the text from your notes or email and paste it into the box.