Duplicate Line Marker

This tool helps you quickly analyze text to identify and count duplicate lines. It’s an ideal utility for data cleaning, code review, or any task that involves checking for redundancy within a text file.

How to Use the Duplicate Line Marker

1. Enter Your Text: Paste the text you want to analyze into the input field.
2. View Summary: The tool automatically processes the text and provides a summary of its contents:
   1. Total Lines: The total number of lines in the text you provided.
   2. Unique Lines: The number of lines that appear only once in the text.
   3. Duplicate Lines: The number of distinct lines that have one or more duplicate occurrences. Even if a single line is repeated multiple times, it is counted as only one “duplicate line.”
3. Filter Results: Below the summary, you have three buttons to control what is displayed in the main output field:
   1. Show All Lines: Displays the original text as you entered it.
   2. Show Unique Lines: Filters the text to show only the lines that appear a single time.
   3. Show Duplicate Lines Only: Displays a list of only the lines that have at least one duplicate, showing each unique duplicate line once.