Text & Writing Utilities · Free tool
Duplicate Line Remover
Remove duplicate lines from any text. Case-insensitive, whitespace-trimmed, or strict modes. Free.
Updated May 2026
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What it does
Strip duplicate lines from any block of text. Multiple normalization options because "duplicate" means different things — a CSV column wants exact match, an email list wants case-insensitive, a notes file wants whitespace-trimmed.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/duplicate-line-remover" width="100%" height="720" frameborder="0" loading="lazy" title="Duplicate Line Remover" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Paste your lines into the input.
- Tick the normalization options that match your use case.
- Copy the deduplicated output.
Frequently asked questions
- Why are emails like ALICE@example.com and alice@example.com sometimes treated as duplicates?
- When 'Ignore case' is on, they compare equal. Email addresses are case-insensitive in the local part for most providers, so this is usually what you want for cleaning a list.
- Does it preserve the first or last occurrence?
- First occurrence. The line that appears earliest in the input is kept; later duplicates are dropped.
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