How to Add Line Numbers to Text (For Code and Documents)

To add line numbers to text, use an online line number tool that prepends numbers to each line with customizable separators. Our Add Line Numbers tool numbers your text instantly with options for starting number, separator style, and padding.

Why Add Line Numbers

Line numbering is useful in many contexts:

Code review — refer to specific lines when discussing code
Legal documents — contracts and legal papers often use line numbering
Technical documentation — enable precise references to content
Data analysis — number rows in datasets for easy reference
Educational materials — help students follow along with numbered lines
Error reporting — report exact line numbers for bugs or issues
Printed documents — make it easy for readers to reference specific sections

Line Numbering Options

Option	Description	Example
Starting number	Begin from any number (default: 1)	1, 10, 100
Separator	Character between number and text	`.` , `:` , `)`
Padding	Leading zeros for alignment	001, 002, 003
All or non-empty	Number all lines or only lines with content	Skips blank lines optionally

Examples

Default (number + period + space):

1. First line
2. Second line
3. Third line

With colon separator:

1: First line
2: Second line
3: Second line

With padding (3 digits):

001. First line
002. Second line
003. Third line

How to Add Line Numbers Online (Step-by-Step)

Open the Add Line Numbers tool
Paste your text into the input area
Choose your options:
- Starting number (default: 1)
- Separator (default: . )
- Padding (optional)
- Number all lines or non-empty only
The numbered text appears instantly
Copy the result

Use Cases

Code snippets — number lines for code review feedback
Contracts — line-numbered legal documents for precise referencing
Transcripts — interview or speech transcripts with line numbers
CSV preview — number rows when reviewing data
Poetry — traditional line numbering for poems
Agendas — numbered meeting agendas for easier navigation

FAQ

Can I start numbering from a different number?

Yes. The tool allows you to set any starting number. This is useful when continuing numbering from a previous section.

Does the tool number blank lines?

By default, blank lines are numbered. You can choose the “Non-empty lines only” option to skip blanks.

Can I use custom separators?

Yes. You can set any separator text between the line number and the line content.

What is padding for?

Padding adds leading zeros so all numbers have the same width. This keeps numbers aligned visually, especially in documents with many lines.

Is this the same as a numbered list in Word?

Line numbers appear at the start of each line. Numbered lists in Word automatically increment and renumber when items are added or removed.

Try our free Add Line Numbers tool to number lines in your text for code review, documents, and data processing.