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Line Numberer

Add line numbers to text for code and logs

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About This Tool

The Line Numberer quickly adds line numbers to code, logs, and list text. It supports custom start numbers, step increments, delimiters, optional empty line skipping, and zero-padded formatting to meet various layout needs. All operations are performed locally in your browser — your text content is never uploaded to any server.

Key Features

Quick Preview

Use Cases

text

Frequently Asked Questions

How do I set the starting line number?

Enter your desired starting number in the 'Start Line Number' field, which defaults to 1. You can start numbering from any number, such as 10 or 100.

What does the step increment do?

The step determines how much the line number increases by. The default step is 1 (1, 2, 3…), but setting it to 2 produces a sequence like 1, 3, 5…, useful for scenarios requiring spaced numbering.

What does zero-padding mean?

Zero-padding adds leading zeros to line numbers to reach a specified width. For example, with a padding width of 3, line numbers display as 001, 002, 003…, keeping all numbers equal width and aligned — ideal for texts with many lines.

What is the skip empty lines feature for?

When enabled, empty lines are not assigned line numbers — numbering only increments for lines with content. This keeps line numbers compact and continuous when processing code or logs with many blank lines.

Can I customize the delimiter between line numbers and text?

Yes. Set your preferred delimiter format in the 'Delimiter' field — the default is '. ' (dot followed by space). You can also use colons, closing parentheses, or other symbols like ': ' or ') '.