Paste any text and instantly find, count, and group all duplicate lines. No signup, no upload — everything runs privately in your browser.
Three simple steps to group and analyze duplicate lines in any text.
Copy any text content — logs, lists, CSV data, code snippets, or emails — and paste it into the input box. The tool accepts any plain text format.
Toggle case sensitivity, whitespace trimming, empty line filtering, and sort preferences to fine-tune how duplicates are detected and displayed.
Click "Group Duplicates" to instantly see each unique line with its occurrence count. Copy, download, or remove duplicates with one click.
The Group Duplicate Lines tool by ToolGalaxy is a powerful, browser-based utility designed to help you quickly identify, count, and organize repeated lines in any block of text. Whether you are a developer cleaning up log files, a data analyst deduplicating spreadsheet exports, a content manager removing redundant entries, or a student organizing research notes — this tool saves you significant time and effort.
When you have a large block of text where individual lines may appear multiple times, "grouping duplicates" means the tool scans every line, identifies which lines are identical (or match based on your settings), and then clusters them together. Each group shows the line content along with how many times it appears in the original text. For example, if the word "apple" appears 5 times across different lines, the tool will group them and display "apple — 5 occurrences."
Log File Analysis: Server logs, application logs, and error logs often contain repeated messages. Grouping these lines helps you identify the most common errors or events at a glance.
Email List Cleaning: If you have a list of email addresses with potential duplicates, paste them in and instantly see which addresses appear multiple times.
URL Deduplication: SEO professionals frequently deal with lists of URLs. This tool quickly highlights duplicate links that need to be removed from sitemaps or crawl lists.
Data Preprocessing: Before importing data into databases or spreadsheets, use this tool to identify and handle duplicate records, ensuring data integrity.
Code Review: Developers can paste code to find duplicate function calls, repeated CSS rules, or redundant import statements.
Unlike many online tools that send your data to remote servers, ToolGalaxy processes everything locally in your browser. Your text never leaves your device, making it completely safe for sensitive data such as personal information, confidential logs, or proprietary business data. The tool is optimized for performance and can handle texts with thousands of lines without lag, ensuring a smooth experience even with large inputs.
ToolGalaxy offers a growing collection of free, professional-grade text utilities. Every tool is designed with a clean interface, fast performance, and real practical value. No registration, no hidden fees, no data collection — just reliable tools that work when you need them. Bookmark this page and return whenever you need to group duplicate lines quickly and efficiently.
Everything you need to know about the Group Duplicate Lines tool.
It scans your text, finds all lines that appear more than once, groups them together, and shows how many times each line occurs. You can copy or download the results.
Yes, ToolGalaxy's Group Duplicate Lines tool is 100% free with no signup, no usage limits, and no watermarks on your output.
Yes, it handles texts with thousands of lines efficiently. Processing happens entirely in your browser, so performance depends on your device but works well for most practical use cases.
Yes, enable the "Case Insensitive" checkbox option before clicking "Group Duplicates." This will treat "Hello", "hello", and "HELLO" as the same line.
Absolutely. All text processing happens locally in your browser. No data is sent to any server, logged, or stored. Your text remains completely private.
You paste plain text directly into the input box. You can copy content from .txt, .csv, .log, .json, .xml, or any text-based file. The output can be downloaded as a .txt file.
Yes! Click the "Remove Duplicates" button to generate a clean version of your text with only unique lines, keeping the first occurrence of each line.