Line Deduplicator
Text & Code · Free Online Tool
Remove duplicate lines, keep first or last occurrence.
First or Last
Choose whether to keep the first or last occurrence of each duplicated line.
Live Stats
See unique and removed counts update in real time as you edit or change options.
Case-Aware
Toggle case sensitivity to control whether "Apple" and "apple" count as the same line.
How to Use Line Deduplicator
- 1Enter or paste your text or code into the input area.
- 2Choose the desired operation (format, convert, analyze, etc.).
- 3Click the action button to process.
- 4Copy the result from the output area.
Features
- ✓100% free — no signup, no subscription, no ads
- ✓Runs entirely in your browser — data never leaves your device
- ✓Fast and lightweight — instant results
- ✓Cross-platform — works on desktop, tablet, and mobile
Frequently Asked Questions
Can I format code in different styles?
Yes, the SQL Formatter and other code tools support multiple formatting options and indentation styles.
Is regex testing case-sensitive?
The Regex Tester supports case-sensitive and case-insensitive matching, along with global and multiline flags.
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Learn the concept
Learn the concept
Understand the programming ideas behind this tool.