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Paste your text below for processing. Supports multi-line text.
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Paste your text below for processing. Supports multi-line text.
Processed text will appear below
This text line processor is simple yet powerful. Here is a detailed guide to help you get started quickly:
Paste or type your text into the input box. The tool supports any multi-line text. It automatically displays statistics including total lines, non-empty lines, and character count below the input area. Select any processing function button and the result will appear in the output area below.
Remove Empty Lines: Click the "Remove Empty" button to automatically strip all lines that contain only whitespace characters, keeping only lines with actual content. This is especially useful when cleaning up content copied from web pages or log files.
Remove Duplicates: Click the "Deduplicate" button to keep only the first occurrence of each line and remove subsequent identical duplicates. Deduplication is based on exact line matching, including all spaces and punctuation.
Sorting: Click "Sort Asc" or "Sort Desc" to alphabetically sort your text lines. The tool uses the browser's built-in sorting algorithm, which correctly handles mixed-language content including English, Chinese, and other scripts.
Reverse Order: Click the "Reverse" button to completely reverse the order of all lines. The first line becomes the last and vice versa.
Enter a keyword in the "Filter Keyword" field and click "Filter Keep" or "Filter Remove". The former keeps only lines containing the keyword, while the latter removes lines containing it. You can chain multiple filter operations to achieve complex data filtering needs.
Before each operation, the current content is automatically saved to a history buffer. Click the "Undo" button to revert to the previous state. History keeps up to 20 steps, allowing you to backtrack through multiple operations.
The text line processor has a wide range of applications in daily work and development. Here are several typical use cases:
When working with raw data exported from Excel, databases, or web pages, you often encounter empty lines, duplicates, and extra whitespace. This tool quickly cleans up data by removing empty lines and duplicates, standardizing formats, and preparing the data for analysis. Examples include cleaning email lists of duplicate addresses, organizing customer lists, and processing CSV export data.
Developers and operations engineers frequently need to filter, sort, and deduplicate system logs. Use the "Filter Keep" feature to extract lines containing specific error keywords, use "Deduplicate" to quickly identify repeated error messages, and use sorting to group related log entries together.
In writing and editing workflows, text often needs formatting adjustments. Examples include alphabetically sorting unordered lists, removing extra empty lines to make text more compact, adding line numbers to code snippets for reference, and converting text to all uppercase or all lowercase.
Text line processing operates on a per-line basis. In computing, line separators typically come in three forms: LF (line feed, \n, used by Unix/Linux/macOS), CR (carriage return, \r, used by old Mac systems), and CRLF (\r\n, used by Windows). This tool automatically detects and handles all three line separators, ensuring cross-platform compatibility.
This tool uses JavaScript's localeCompare method for sorting, which is a Unicode-standard string comparison algorithm. For English text, it sorts alphabetically; for Chinese, it sorts by pinyin; for numbers, it sorts numerically; and for mixed content, it follows Unicode code point order.
All processing happens locally in your browser with no server involvement, meaning speed depends entirely on your device's performance. Modern browsers can process tens of thousands of lines in milliseconds. For files exceeding 100,000 lines, consider processing in batches or using dedicated command-line tools like awk, sort, and uniq.
For more complex text processing needs, check out these related tools: Text Deduplication Tool (focuses on duplicate statistics), Text Diff Tool (compares differences between two texts), and Text Analyzer (word frequency and text analysis). These tools complement this one and cover most daily text processing needs.
The tool supports removing empty lines, removing duplicate lines (keeping the first occurrence), sorting lines in ascending or descending order, reversing line order, trimming whitespace from each line, adding line numbers, filtering lines that contain specific keywords, keeping only lines that contain specific keywords, and converting text to uppercase or lowercase.
No. All processing happens entirely within your browser. Your data never leaves your device or gets uploaded to any server, ensuring complete privacy and security. You can safely process sensitive data.
The tool can handle tens of thousands of lines depending on your device's memory and browser capabilities. In general, processing up to 100,000 lines is effortless. For extremely large files, consider processing in batches.
Deduplication matches entire lines exactly, including all spaces and punctuation. If two lines are completely identical, the second occurrence is removed while the first one is kept.
Yes. The sorting function uses the browser's localeCompare method, which properly handles Unicode characters including Chinese, Japanese, Korean, and other scripts. Mixed-language content is also supported.
Yes. The tool automatically saves your current content to a history buffer before each operation. You can click the Undo button to revert to the previous state. History keeps up to 20 steps.
Yes. Click the "Remove Numbers" button and the tool will intelligently detect and strip the leading numbers and separators from each line, restoring the original text.
The current version supports simple keyword filtering, not regular expressions. If you need regex filtering, try our Online Regex Tester for preprocessing.