Add Line Numbers to Text — Free Online

1. Paste your text into the input area. The tool accepts any plain text: code snippets, legal documents, poetry, transcripts, or data files. Use the example button to see a demo.

2. Choose your options. Set the starting number, pick a separator style (period, parenthesis, tab, or colon), and toggle zero padding for uniform width. Switch to remove mode to strip existing numbers.

3. Copy the result. The numbered output appears instantly below the input. Click the Copy button to copy the result to your clipboard for pasting into documents, emails, or code editors.

4. Remove numbers when needed. Switch to Remove mode to strip line numbers from previously numbered text. The tool detects common formats automatically.

Line numbers are essential for referencing specific parts of a document. Whether you are reviewing code, editing legal contracts, discussing poetry in a literature class, or collaborating on scripts, line numbers let everyone point to the exact same place in the text. Without them, phrases like “near the middle of the page” lead to confusion and wasted time.

Code review and programming: When sharing code snippets in emails, chat, or documentation, adding line numbers makes it easy to reference specific lines. Code review comments like “check line 42” are far more precise than “look at the function near the top.” Many style guides recommend numbered code blocks in technical documentation.

Legal and academic documents: Legal briefs, court transcripts, depositions, and academic manuscripts use line numbering for precise citation. Zero-padded numbers maintain consistent formatting across long documents, and the colon or period separators match standard legal formatting conventions.

Creative writing and education: Poetry analysis, screenplay review, and essay workshops all benefit from line numbers. Teachers can reference “line 14” instead of reading the entire passage. Students can cite specific lines in their analysis without ambiguity.

Data processing: Adding line numbers to CSV files, log outputs, or configuration files helps track entries during debugging. Tab-separated numbering integrates cleanly with spreadsheet software, and zero padding ensures proper sorting in file systems.

This tool processes everything locally in your browser. No data is uploaded, no account is required, and there are no limits on text length. Paste, number, copy, and move on.