What does "case-sensitive" mean here?

When enabled, "Apple" and "apple" are treated as different lines and both kept. When disabled, they are considered duplicates and only the first occurrence is kept.

What does "Trim whitespace" do?

It strips leading and trailing spaces from each line before comparison, so " apple" and "apple " are treated as the same line.

Will it remove blank lines?

Only if you check "Remove blank lines". By default blank lines are deduplicated like any other line — so multiple blank lines become one.

How many lines can it handle?

The tool processes everything in your browser and in PHP on the server. There is no hard limit, but very large inputs (millions of lines) may be slow.

Does it preserve the original order?

Yes, unless you check "Sort results". The first occurrence of each line is kept in its original position.

Can I remove duplicate lines from an Excel column?

Yes. Copy the column from Excel or Google Sheets, paste it here, remove the duplicates, then paste the unique list back. The tool works on any line-separated text.

Remove Duplicate Lines

Name: Remove Duplicate Lines
Availability: InStock
Author: Nham Vu

Paste any list, choose your options, and get a clean deduplicated result with stats on how many lines were removed.

Input & Options

Lines

Processing Options

Case-sensitive "Apple" and "apple" are different

Trim whitespace Trim each line

Remove blank lines Skip empty lines

Sort results Sort alphabetically

Results

Configure on the left, then click Process to begin.

Summary

Paste any list, choose your options, and get a clean deduplicated result with stats on how many lines were removed.

How it works

Paste your list of lines into the input field.
Configure options: case sensitivity, trim whitespace, remove blank lines, sort output.
Click Process to deduplicate.
Copy the results and see the stats showing how many lines were removed.

Use cases

Clean up email lists by removing duplicate addresses.
Deduplicate imported CSV data before analysis.
Remove duplicate keywords from an SEO list.
Trim repeated log entries from server output.

Frequently Asked Questions

Last updated: 2026-06-25 · Reviewed by Nham Vu