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Quickly count the frequency of duplicate lines in your text. Ideal for data cleaning, log analysis, and text processing.
Enter text to start counting
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Look up exact millimeter dimensions for D0 to D6 series paper based on the GB/T 19999-2003 national standard, suitable for book, magazine, and office paper design.
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When you need to find out which items are duplicated in a list of text lines and how many times they appear, manual counting is both tedious and error-prone. This tool automatically compares your input text line by line and calculates the frequency, outputting a clear list of each line and its corresponding occurrence count. The core processing object of the Duplicate Line Counter is each independent text unit separated by line breaks, and the statistical principle is based on hash mapping for frequency accumulation.
Q: Are empty lines and spaces counted when inputting text?
A: Yes. The tool treats every line with characters, as well as completely blank lines, as independent units. For example, two consecutive empty lines will be counted as "(Empty Line): 2".
Q: How much text can this tool handle?
A: The tool runs entirely in your browser, so its processing capacity is limited by your device's memory. It can smoothly handle everyday data cleaning or log analysis tasks (e.g., tens of thousands of lines). For extremely large volumes of text (e.g., hundreds of thousands of lines), we recommend processing them in batches.
Please note that the tool processes plain text. HTML tags and special formatting characters will be treated as regular text during the counting process. The results are displayed in the order of their first appearance, not sorted by frequency. For text containing sensitive information, please use it in a trusted environment; this tool processes everything locally and does not send your data to any servers.
A typical application during data cleaning is counting the frequency of user-submitted options or keyword lists. For example, if you input "Apple Banana Apple Orange Banana Apple", the tool will output "Apple: 3 Banana: 2 Orange: 1". This helps you quickly identify the most common entries. Please note that this tool performs exact matching. Differences in capitalization and leading/trailing spaces will cause "Apple" and "apple" to be counted as two different items. If you need case-insensitive counting, we recommend standardizing and preprocessing your text first.
