Remove Duplicate Lines
Paste a list of lines and instantly remove exact duplicates, keeping the first occurrence of each line with optional case sensitivity.
Result
Your result will appear here.
How to use Remove Duplicate Lines
- 1Paste your list of items or text lines into the input area.
- 2Toggle the "Case sensitive" checkbox depending on whether "Apple" and "apple" should be treated as duplicates.
- 3View the cleaned unique list and click Copy to copy the result.
Key features
Order-Preserving Deduplication
Maintains the original chronological sequence of entries, keeping the first occurrence of each unique line.
Configurable Case Sensitivity
Toggle case-sensitive matching for code symbols/hashes or case-insensitive matching for email/word lists.
Duplicate Counter Metric
Displays the exact count of removed duplicates in real time alongside the cleaned output.
High-Performance Set Processing
Utilizes JavaScript Sets for fast O(N) deduplication across thousands of lines.
Examples & use cases
Email List Cleaning
Deduplicating subscriber contact entries
admin@example.com support@example.com admin@example.com info@example.com
admin@example.com support@example.com info@example.com (1 duplicate removed)
Code Import List Cleanup
Removing repeated package imports
import React from "react";
import { useState } from "react";
import React from "react";import React from "react";
import { useState } from "react"; (1 duplicate removed)Frequently asked questions
Helpful guides & tutorials
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