Text Tools
Remove Duplicate Lines
Instantly remove duplicate lines from text lists. Filter unique items, sort results, and clean up your data. Case-sensitive and insensitive options available.
Use Remove Duplicate Lines to get instant results without uploads or sign-ups. Everything runs securely in your browser for fast, reliable output.
Your results will appear here.
About this tool
Cleaning up lists is a common task. Whether you have a list of emails, URLs, or inventory items, duplicates can cause errors and waste space.
Our Remove Duplicate Lines tool does exactly what it says: it scans your text and deletes any line that appears more than once. It keeps the first occurrence and removes the rest.
You can also sort the final result alphabetically to make it easier to read. All processing happens on your device, so you can safely clean large files containing sensitive info.
Usage examples
Simple List
Removing exact duplicates
Apple Banana Apple → Apple Banana
Case Insensitive
Treating Apple == apple
Apple apple → Apple
How to use
- Paste your list of text into the input box.
- Select "Case Insensitive" if you want "Apple" and "apple" to be treated as duplicates.
- Select "Trim Whitespace" to ignore spaces around lines.
- The tool automatically generates the unique list.
- Click "Copy" to save your cleaned list.
Benefits
- Instant Deduplication
- Supports Case Sensitivity settings
- Trims extra whitespace
- Sorts output alphabetically (A-Z or Z-A)
- Shows count of removed lines
- Works with large lists (10,000+ lines)
FAQs
How does it find duplicates?
The tool uses a Hash Set algorithm to strictly compare each line of text against previous lines. If a match is found based on your settings (case-sensitive or insensitive), the duplicate line is removed. The first occurrence of each unique line is preserved.
Does it keep the original order?
Yes! Unless you select a sorting option, the unique lines will remain in their original relative order. This is useful when the sequence of items matters, such as ordered lists, instructions, or chronological data.
Is it case sensitive?
By default, no. "Apple" and "apple" are treated as the same line. Enable "Case Sensitive" if you want them treated as different lines. This is useful when case matters, such as when dealing with code, product names, or proper nouns.
Can I sort the results?
Yes! After removing duplicates, you can sort results alphabetically (A-Z or Z-A) or by length (shortest first). Sorting makes it easier to find specific items in long lists and presents data more professionally. Choose "Keep Original Order" if sequence matters.
What types of lists can I deduplicate?
Any text-based list works: email addresses, URLs, names, product codes, keywords, file paths, or data exports. The tool processes each line separately, so one item per line. Perfect for cleaning CSV exports, email lists, log files, or any list with unwanted duplicates.
Is there a size limit?
The tool efficiently handles lists with 10,000+ lines. All processing happens in your browser, so very large lists (100,000+ lines) may take a few seconds but will work. If you experience slowness with massive lists, try breaking them into smaller chunks and combining the results.
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