How to Add Line Numbers to Text Online (Free)

To add line numbers to text, paste your text into the ByteTools Add Line Numbers tool, and every line is instantly prefixed with a running number — 1, 2, 3 and so on — that you can copy or download. You can also set a custom starting number, zero-pad the digits for neat columns, and pick the separator that follows each number, all without installing anything or sending your text to a server.

This guide walks through the tool from paste to copy, explains each option, and shows why doing it in the browser keeps your text private.

What the tool does

The Add Line Numbers tool reads your text line by line and adds a sequential number and separator to the front of each one. The body of every line is left untouched — only a prefix is added — so the result is your original content with a clean numbering column in front of it. Blank lines are counted too, which means the numbers always match the true line positions in your source.

Typical output looks like this:

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

Step-by-step: numbering your text

1. Paste or type your text. Put one item per line — a list, a code snippet, log output or any document. The numbering updates live as you type.
2. Set the starting number. The default is 1, but you can enter any value if you are continuing from a previous page or a specific line range.
3. Enable zero-padding (optional). Turn this on when you want the numbers to line up in a straight column, so 1 through 10 become 01 through 10.
4. Choose a separator. Pick the character that follows each number: a dot, colon, parenthesis, tab or plain space.
5. Copy or download. Review the live preview, then click Copy to send the numbered text to your clipboard or Download to save it as a .txt file.

Choosing the right options

The three settings — start value, zero-padding and separator — cover almost every numbering need. This table shows how each affects the output.

Option	What it changes	Example output
Start number	The first number in the sequence	5. line, 6. line
Zero-padding	Adds leading zeros for aligned columns	01) line, 02) line
Dot separator	Classic numbered-list look	1. line
Colon separator	Log or reference style	1: line
Tab separator	Pastes cleanly into spreadsheets	1 line

Why do it in your browser

All numbering happens locally in your browser with JavaScript. Your text is never uploaded, stored or logged, so the tool is safe for confidential lists, unreleased code and private drafts. Because nothing depends on a server round-trip, results appear instantly, and — as a Progressive Web App — the tool keeps working even when you are offline.

Try the Add Line Numbers to Text tool — free and 100% in your browser.

FAQ

How do I number only some of the lines?

The tool numbers every line in the box, so paste just the portion you want numbered. If you need to renumber a section that continues a larger document, set the starting number to match where the previous section left off.

Will the numbers copy correctly into Word or Google Docs?

Yes. The copied result is plain text with the number, separator and your content on each line, so it pastes into any editor. Use the tab separator if you want the numbers to sit in their own column when pasted into a table or spreadsheet.

What separator should I use for code listings?

A colon or a plain space usually reads best for code, and turning on zero-padding keeps the numbers aligned so longer files stay tidy. For prose or checklists, the dot separator gives the familiar numbered-list appearance.

Does it handle very long text?

Because processing runs on your own device, the tool comfortably handles long documents and log files. Larger inputs simply take a moment longer to render in the live preview.

Related free tools

• Remove Duplicate Lines — clean up a list before you number it.
• Sort Lines — order your lines alphabetically or numerically first.
• Remove Extra Spaces — tidy spacing so numbered output stays neat.
• Find and Replace Text — bulk-edit content across every line.

Built by ByteVancer

ByteTools is a free product of ByteVancer, a software and web development studio that builds web apps, SaaS platforms and custom software. If you need a tool, workflow or product built for your team, explore what ByteVancer can create for you.