Does it preserve the original order?

Yes — with Sort set to 'None', the first occurrence of each item is kept and subsequent duplicates are removed, preserving insertion order.

What does 'Case sensitive' do?

When enabled, 'Apple' and 'apple' are treated as different items and both kept. When disabled (default), they are treated as the same and only the first occurrence is kept.

Can I deduplicate comma-separated values?

The tool works line-by-line. For CSV, split on commas first (using your editor or a text replace), deduplicate, then rejoin. A dedicated CSV tool would handle this more elegantly.

What happens to whitespace?

With 'Trim lines' enabled, leading and trailing spaces are removed before comparison. ' apple ' and 'apple' are treated as the same. Without it, they are different.

Is there a line limit?

No hard limit — all processing runs in your browser. Very large lists (hundreds of thousands of lines) may be slower depending on your device.

Remove Duplicate Lines — Free Online Deduplicator | Toolivon

Remove Duplicate Lines

Deduplicate any list with case sensitivity, sort, and trim options. Real-time output with duplicate count.

Case sensitiveTrim linesRemove empty

Sort:

Input lines

Unique lines

Duplicates removed

Input — one item per line

Output (deduplicated)

apple
banana
orange
grape

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How to Remove Duplicate Lines

1
Paste your list
Paste any list of items into the left panel — one item per line.
2
Configure options
Toggle 'Case sensitive' to treat 'Apple' and 'apple' as different (or the same). Toggle 'Trim lines' to strip leading/trailing whitespace. Toggle 'Remove empty' to skip blank lines.
3
Choose sort order
Select None to preserve original order, A → Z for ascending, or Z → A for descending.
4
Review the output
The right panel shows the deduplicated list in real time. The stats bar shows how many duplicates were removed.
5
Copy the result
Click 'Copy' to grab the deduplicated list.

Frequently Asked Questions

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