Duplicate Line Remover

Remove duplicate lines from a list of text. Optionally keep the original order or trim whitespace.

Case sensitive Trim whitespace Drop empty lines

Input

apple
banana
apple
cherry
banana
date

Output

Features

Before/after line count

Preserve order

Case sensitive/insensitive

Show removed lines

How to Use

1. Paste your text into the input box (one item per line).

2. Toggle case-sensitivity and trim options as needed.

3. Click Remove Duplicates — the deduplicated result appears on the right.

About this tool

Lists collected from spreadsheets, logs, exports or copy-paste are full of repeats. This tool removes duplicate lines while keeping the first occurrence of each one in its original position, so the order of your list is preserved rather than sorted. Options decide what counts as "the same": case sensitivity treats "Apple" and "apple" as different or equal, trimming ignores leading and trailing spaces that are invisible but make lines differ, and dropping empty lines tidies the result. A summary shows how many lines went in, how many came out and how many were removed. It is useful for cleaning email lists, keyword sets, tag lists, file paths and log entries before importing them elsewhere.

Frequently Asked Questions

Which copy of a duplicate is kept?

The first occurrence is kept in its original place and later repeats are removed. The overall order of the remaining lines does not change, so the output is not sorted.

Why were two lines that look identical not merged?

They probably differ in invisible characters such as trailing spaces, tabs or a non-breaking space, or only in letter case. Turn on "Trim whitespace" and turn off "Case sensitive" to treat them as the same.

Does trimming change the lines in the output?

Trimming is used to compare lines and also removes the leading and trailing spaces from the lines that are kept. Spaces inside a line are left untouched.

Can it remove duplicate words instead of lines?

It works line by line. To deduplicate words or comma-separated values, put each item on its own line first, for example by replacing commas with line breaks in your editor.

How many lines can it process?

The work happens in your browser, so tens of thousands of lines are handled quickly on a typical computer. Extremely large files are better processed with a command-line tool such as sort -u or awk.