Add Line Numbers

How do I use the Add Line Numbers?

1. 1

   Paste text.

2. 2

   Choose the starting number.

3. 3

   Copy the numbered output.

What is the Add Line Numbers?

The Add Line Numbers tool prefixes every line with a padded line number so readers can reference exact lines. Perfect for code reviews, book quotes and technical documentation.

Who is the Add Line Numbers for?

Developers preparing code reviews, technical writers, teachers quoting passages, and legal teams referencing clauses.

Why use the Add Line Numbers?

• Padded, right-aligned numbers.
• Configurable start number.
• Instant preview.
• Preserves original line content.
• Runs offline.

When should I use the Add Line Numbers?

• Code review annotations.
• Quoting book passages by line.
• Legal contract references.
• Teaching materials.
• Bug reports with exact lines.

Is the Add Line Numbers safe and private?

Yes. This tool runs entirely inside your browser - your text is never uploaded, stored on our servers or shared with third parties. You can even disconnect from the internet after the page loads and it will keep working. That makes it safe for confidential notes, drafts, private messages and unpublished work.

How do I get the best results from the Add Line Numbers?

• Best viewed in a monospace font.
• Use start-at-100 for consistent width in short files.
• Combine with Column Splitter for multi-column output.
• Pair with Remove Line Numbers to undo.

Frequently asked questions

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