Remove Duplicate Lines

Remove duplicate lines and keep unique lines

Use this tool to remove duplicate lines from a list or block of text. It keeps the first occurrence of each line and preserves original order—handy when you need unique lines without sorting.

Ignore case, ignore whitespace, remove empty lines

By default lines are compared exactly after normalizing CRLF, LF, and CR. Optionally ignore letter case or leading/trailing whitespace for matching only; retained lines keep their original spelling and spaces. A separate option removes all blank or whitespace-only lines.

Browser-local processing and privacy

Deduplication runs in your browser. Your text is not sent to BizNavi Hub servers to compute results, and is not stored by this tool for later reuse.

Practical size limits

Very large pastes may be slower. Soft guidance starts around 500,000 characters; a hard limit of 1,000,000 characters and a line-count safety limit protect the page. There is no server fallback.

Business use cases

• Clean duplicate entries from pasted contact or SKU lists.
• Deduplicate log lines or checklist items before sharing.
• Remove repeated FAQ or localization strings while keeping first wording.

FAQ

Does my text leave the browser?

No. Deduplication runs locally; we do not upload your text to compute results.

Which duplicate is kept?

The first occurrence. Later matches are removed. Original order of retained lines is preserved.

What do ignore case and ignore whitespace do?

They change comparison keys only. The kept line is still the original first text you pasted.

How are empty lines handled?

By default one empty line is kept if duplicates exist. Enable Remove empty lines to drop all blank or whitespace-only lines.

Which languages are supported?

The live UI is available in Japanese, English, German, French, Dutch, and Spanish. Polish is not live yet.