TinyToolHub
Remove Duplicate Lines
Remove duplicate lines from your text while preserving the original formatting. Choose case-sensitive or case-insensitive matching.
Our free duplicate line remover tool helps you clean up text by removing duplicate lines while preserving the original formatting. Perfect for cleaning up lists, removing redundant data, or processing text files with repeated content.
Key Features:
- Case-sensitive matching: Choose whether "Apple" and "apple" are considered duplicates
- Preserve formatting: Original line formatting and spacing are maintained
- First/Last occurrence: Choose which duplicate to keep
- Real-time statistics: See how many duplicates were removed
- Large text support: Handle files with thousands of lines
- Copy to clipboard: Easy export of cleaned text
Common Use Cases:
- Cleaning up email lists and contact databases
- Removing duplicate entries from CSV files
- Processing log files and removing repeated entries
- Cleaning up code files with duplicate imports
- Organizing lists and removing redundant items
- Data preprocessing for analysis
What's the difference between case-sensitive and case-insensitive matching?
Case-sensitive matching treats "Apple" and "apple" as different lines. Case-insensitive matching treats them as duplicates. Choose based on whether capitalization matters for your data.
Should I keep the first or last occurrence of duplicates?
Keeping the first occurrence preserves the original order and is usually preferred. Keeping the last occurrence might be useful if later entries have updated information.
Does this tool preserve empty lines?
Yes, empty lines are treated like any other line. If you have multiple empty lines, only one will be kept (unless you want to preserve all empty lines, in which case you should remove them manually first).
Can I process very large files?
The tool can handle large amounts of text, but very large files (over 1MB) may cause performance issues in your browser. For best performance, consider processing files in smaller chunks.
Is my data safe when using this tool?
Yes, all processing happens entirely in your browser. Your text is never sent to our servers or stored anywhere. The tool works completely offline once loaded.