Remove Duplicate Lines

About this tool

This tool removes duplicate lines from text. Paste a list — e-mail addresses, keywords, URLs, log entries — and every repeated line is deleted, keeping only the first occurrence in the original order.

How to use it

1. Paste your list into the first box, one item per line.
2. Tick "Ignore case" if entries that differ only in capitalization should count as the same line.
3. Copy the de-duplicated list from the result box.

Common uses

• De-duplicate e-mail lists before sending a mailing
• Clean keyword lists for SEO or ad campaigns
• Remove repeated URLs from a scraped or exported list
• Reduce noisy log output to its unique lines
• Merge two lists: paste them one after another and duplicates between them disappear automatically

Frequently asked questions

Does the order of my list change?

No. Lines stay in their original order; only the repeats after the first occurrence are removed. Nothing is sorted.

How are duplicates detected?

Two lines count as duplicates when they match exactly, character for character. With "Ignore case" enabled the comparison is case-insensitive, so "Apple" and "apple" become one line. Note that invisible differences such as trailing spaces make lines distinct — run the text through Remove Extra Spaces first if your list might contain them.

How large can my list be?

Tens of thousands of lines are no problem — processing happens instantly on your own device.

Is my list private?

Yes. Everything runs in your browser — your text is never uploaded or stored anywhere.