Remove Duplicate Lines

Paste a list to strip out repeated lines. Optionally ignore case, trim whitespace, and sort the result.

Input (one item per line)

Case-sensitive Trim whitespace Sort output Drop blank lines

Result

🔒 Nothing you enter is sent anywhere or stored. All processing happens in your browser.

How it works

This tool scans your text line by line and keeps only the first occurrence of each line, discarding later repeats. It's ideal for cleaning up email lists, keyword lists, CSV columns, or any data where each entry should appear once.

Four options control how duplicates are matched. Trim whitespace removes leading and trailing spaces before comparing, so "apple" and " apple " are treated as the same. Case-sensitive, when unticked, treats "Apple" and "apple" as duplicates; tick it to keep case differences distinct. Drop blank lines removes empty rows, and Sort output alphabetizes the result for easier scanning.

The original order is preserved unless you choose to sort. All processing is done in your browser, so even large or sensitive lists never leave your device.

Examples

Input apple / Banana / apple (case-insensitive) → apple / Banana

With "Case-sensitive" on, Apple and apple are kept as two separate lines.

Turn a messy keyword dump into a clean, sorted, de-duplicated list in one click.

Frequently asked questions

Does it keep the first or last duplicate?

The first occurrence is kept and later repeats are removed, so the earliest position of each unique line is preserved.

Is the original order maintained?

Yes, unless you tick 'Sort output'. Without sorting, lines stay in their original order minus the duplicates.

What does 'trim whitespace' do?

It ignores leading and trailing spaces when comparing lines, so entries that differ only by stray spaces are treated as duplicates.

Can it handle very large lists?

Yes. Processing runs locally and comfortably handles tens of thousands of lines on most devices.