Remove Duplicate Lines
Remove duplicate lines from any list or text while keeping the first occurrence and the original order. Ideal for cleaning up lists, logs, emails, and exported data. Options for case sensitivity and trimming whitespace before comparing.
Whether you call it remove duplicate lines or delete duplicate lines, this free tool handles it instantly in your browser.
Options
Example usage
Example input
apple banana apple cherry banana
Example output
apple banana cherry
Batch Processing
Enter multiple inputs, one per line. Each line will be processed separately.
Why this tool?
Everything runs right in your browser — no uploads, no sign-up, no waiting. Your text never leaves your device.
Quick tips
- •Outputs update live as you type.
- •Use the sticky copy button to grab results quickly.
- •Bookmark this page for fast access.
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How it works
- Paste your text or list with one item per line.
- Each line is compared and repeats are removed, keeping the first occurrence.
- Use the options to ignore case or surrounding spaces when comparing.
Use cases
Where duplicate lines come from
Duplicates rarely appear one at a time; they arrive in batches from predictable sources: merging two exported lists (email subscribers from two campaigns), copy-pasting log output that repeats headers, spreadsheet exports where a join multiplied rows, and iterative edits where a paste landed twice. Deduplicating before importing anywhere is cheap insurance — most email tools, for instance, count list size against your billing tier.
This tool keeps the first occurrence and preserves original order, which matters when your list is already sorted by priority or date: the earliest (usually canonical) entry survives.
Case sensitivity and whitespace: the two dedupe traps
Two lines can be "the same" to a human and different to a computer. "Apple@Example.com" and "apple@example.com" are one mailbox but two strings — leave case-insensitive matching on for emails, usernames, and tags. Trailing spaces are the sneakier trap: "apple " and "apple" look identical on screen; enable the trim option when your list came out of a spreadsheet, where stray spaces are endemic. For a fully normalized list, run Remove Extra Spaces first, dedupe second, and sort last with the Alphabetical Order tool.
Cleanup
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FAQ
How is this different from removing duplicate words?
This tool compares whole lines, not individual words. It keeps the first time a line appears and removes any later exact repeats.
Does it keep the original order?
Yes. Lines stay in their original order, and only later duplicates are removed. Use Sort Lines first if you also want them sorted.
Can it ignore case and spacing?
Yes. Turn on the options to treat differently-cased lines as the same and to ignore leading or trailing spaces when comparing.