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Line Number Adder - Add Line Numbers to Text Online

Add line numbers to each line of text

Custom start
Zero padding
Skip empty
Custom separator
Options
Input Text
Output Result
Usage Guide

What is Line Numbering?

Line numbering tool adds sequential numbers to each line of text, making it easier to reference and locate content in code, logs, and documents.

Common Use Cases

  • • Code line numbers
  • • Log numbering
  • • Document references
  • • List ordering

The Line Number Adder is a versatile text utility that adds sequential numbers to each line of your content. Whether you are preparing code snippets for documentation, numbering log entries for analysis, or creating ordered lists for presentations, this tool offers complete flexibility. Customize the starting number to continue from any point, choose your preferred separator format, enable zero-padding for consistent alignment, and optionally skip empty lines. The real-time preview shows exactly how your numbered text will appear, making it perfect for developers, writers, technical documentation, and anyone who needs professional line-numbered output.

Why Add Line Numbers to Text?

Line numbers serve multiple purposes in text processing. In code reviews, they enable precise references to specific lines during discussions. For legal documents, numbered lines meet formatting requirements and facilitate citations. In educational materials, line numbers help students locate specific passages. Log analysis becomes easier when entries are numbered for tracking. This tool makes adding line numbers instant and customizable.

Customization Options Explained

  • Starting Number: Begin numbering from any integer, useful when continuing from a previous section
  • Separator: Choose between colon, period, parenthesis, or any custom character
  • Zero Padding: Align numbers with leading zeros (01, 02... instead of 1, 2...)
  • Skip Empty Lines: Preserve blank lines without numbering them for better readability

Common Formatting Patterns

Different contexts require different numbering styles. Code typically uses spaces after numbers (1 code). Legal documents use periods (1. text). Academic citations may use brackets [1]. Script and screenplay formats have their own conventions. This tool supports any separator you need for your specific use case.

Command Line Alternatives

For batch processing, Unix commands offer similar functionality: 'cat -n file' adds line numbers, 'nl file' provides more options, and 'awk' can create custom formats. However, this online tool provides instant results without installing software, with a visual interface for non-technical users.

FAQ

Q: Can I number only non-empty lines?

A: Yes! Enable the 'Skip Empty Lines' option. Empty lines will be preserved in the output but won't receive line numbers, and the numbering will continue correctly on the next non-empty line.

Q: How do I get aligned line numbers for large files?

A: Enable 'Zero Padding' to add leading zeros. For example, if you have 100 lines, numbers will appear as 001, 002... 100, ensuring consistent column width and visual alignment.

Q: Can I continue numbering from a previous document?

A: Yes, simply set the 'Starting Number' to the line number where you want to begin. If your previous section ended at line 50, set the starting number to 51.

Q: What separators can I use?

A: You can use any text as a separator. Common choices include ': ' (colon space), '. ' (period space), ') ' (parenthesis space), ' ' (tab or spaces), or custom formats like '| ' for table-style output.

Q: How do I remove line numbers from text?

A: This tool focuses on adding line numbers. To remove existing line numbers, you can use a regex replacement tool. A pattern like '^\d+[.:)]\s*' will match common line number formats at the beginning of each line.