Remove Duplicate Lines
Remove duplicate lines from text instantly. Keep first, last occurrence, or count duplicates with case-sensitive matching and whitespace trimming. Process text instantly in your browser with no software downloads or.
Result
What is Remove Duplicate Lines | Rune
The Remove Duplicate Lines tool instantly detects and eliminates repeated lines from your text. Whether you're cleaning up data exports, log files, or any list with redundancies, this tool offers flexible modes, keep first occurrence, keep last, or count all duplicates.
Features include case-sensitive matching, whitespace trimming, and empty line handling. Handles text of any length with real-time processing and instant output display in the interface. Supports Unicode characters, special symbols, and multiple languages for comprehensive text processing. Copy results directly to your clipboard with a single click for seamless integration into your workflow.
Key Features of Remove Duplicate Lines
Everything you need for professional remove duplicate lines
Multiple Dedup Modes
Choose to keep the first occurrence, last occurrence, or count how many times each line appears for detailed duplicate analysis.
Case Sensitivity Toggle
Switch between case-sensitive and case-insensitive matching to control whether 'Hello' and 'hello' are treated as duplicates.
Whitespace Trimming
Optionally trim leading and trailing whitespace before comparing lines, catching duplicates that differ only by spacing.
Duplicate Details Panel
See exactly which lines were duplicated and how many times, giving you full visibility into the redundancies in your data.
Real-Time Statistics
Track total lines, unique lines, duplicates removed, and reduction percentage as you work.
Auto-Save Progress
Your text and settings are saved locally, so you can close the tab and pick up where you left off.
How to Use Remove Duplicate Lines
Follow these simple steps to get started
Paste Your Text
Paste or type the text containing duplicate lines into the input area.
Configure Options
Select your dedup mode (keep first, keep last, or count) and toggle case sensitivity and whitespace trimming.
Copy Clean Text
The deduplicated result appears instantly. Copy it to clipboard or review the duplicate details panel.
Pro Tips
- Use 'Count Occurrences' mode to identify the most repeated lines in log files or data exports.
- Enable 'Trim whitespace' to catch hidden duplicates that differ only by leading or trailing spaces.
- Turn off case sensitivity when cleaning email lists to catch duplicates like 'User@Email.com' and 'user@email.com'.
- Check the duplicate details panel to understand patterns in your repeated data.
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Frequently Asked Questions
Everything you need to know about Remove Duplicate Lines
Does this tool preserve the original line order?
Yes! When using 'Keep First' or 'Keep Last' mode, the remaining unique lines maintain their original order from your input text. Only the duplicate occurrences are removed.
What does 'Count Occurrences' mode do?
Count Occurrences mode shows each unique line alongside the number of times it appears in your text, formatted as 'count | line'. This is useful for analyzing frequency in data files or logs.
How does case sensitivity work?
When case-sensitive mode is on, 'Hello' and 'hello' are treated as different lines. When turned off, they're considered duplicates. Choose based on whether capitalization matters for your data.
Is there a line limit?
No! The tool handles text of any size, from a few lines to thousands. All processing happens in your browser, so there are no server-side limits.
Can I use this for CSV or TSV data?
Yes, this tool works with any line-based text format. For CSV data, each row is treated as a line. If you need to deduplicate based on a specific column, consider using a spreadsheet tool first.
Does it handle empty lines?
Yes! You can toggle 'Ignore empty lines' to either keep or remove blank lines from your output. This is especially useful when cleaning up text with irregular spacing.
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