Free Online Add Line Numbers Tool

A line-numbering tool prepends "1: ", "2: ", and so on to each line — useful for code snippets, transcript references and legal documents.

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How to Use This Text Tool

  1. Paste your text or code into the input field.
  2. Choose a separator style: "1: ", "1. ", "1) " or "[1] ".
  3. Set the starting number (default 1).
  4. Optionally enable zero-padding to align numbers in a fixed-width column.
  5. Click Copy to send the numbered output to your clipboard.

What Is an Add Line Numbers?

Numbered lines make it possible to point at a specific position during code review ("the bug is on line 42"), legal citation, poetry analysis or transcript editing. Most code editors show line numbers in the gutter, but plain-text pastes lose them — this tool bakes them into the text itself, so the numbers survive copy-paste anywhere.

Configure the separator ("1: ", "1. ", "1) ", "[1] "), the starting number (useful when continuing from a previously-numbered block), and zero-padding so a 100-line file aligns from "001" through "100" in a fixed-width column.

Everything runs locally.

Frequently Asked Questions

What format do line numbers use?
Choose from common separators: '1: text', '1. text', '1) text', '[1] text', or a fully custom format. Optional zero-padding aligns numbers in fixed-width columns.
Why add line numbers?
Use for code sharing ('see line 42'), poetry analysis, legal documents, transcript references, or any content where you need to point to specific lines.
Can I start from a different number?
Yes. Set the starting number to any positive integer (or zero) to begin numbering from there. Useful for continuing a previously numbered block.

Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.

Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.

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