What is the Add Line Numbers to Text?
Add aligned line numbers to any block of text — useful for quoting code or steps.
The tool is part of the Calabi free tools hub — a collection of 99+ browser-based utilities for developers, designers, and content creators. Everything runs client-side: your files and data never leave your device.
How to use the Add Line Numbers to Text
- Step 1: Paste your lines.
- Step 2: Get numbered output.
- Step 3: Copy it.
The tool updates in real time as you interact with it. No button-clicking required for most tools — results appear instantly.
Example
a / b → 1. a / 2. b
Privacy & security
The Add Line Numbers to Text is designed with privacy as a hard constraint, not an afterthought:
- No upload: Your data is processed in your browser's JavaScript engine. No HTTP request is made to any server while you use the tool.
- No account required: The tool works instantly — no email, no sign-up, no cookie consent wall.
- No logging: Calabi does not log what you paste, upload, or generate. The server only delivers the HTML/JS page — it never sees your content.
- Open to inspection: Open your browser's network inspector while using the tool. You'll see zero outbound requests related to your data.
This architecture is particularly important for the Text category of tools, where the inputs often contain sensitive or proprietary information.
Frequently asked questions
Is the Add Line Numbers to Text free?
Yes, completely free with no account required.
Does it upload my data?
No. The Add Line Numbers to Text runs entirely in your browser — your data never leaves your device.
Will it work on mobile?
Yes. The tool works on any modern browser on desktop and mobile.
Can I use this for commercial purposes?
Yes, there are no restrictions on commercial use.
About Text tools
The Add Line Numbers to Text is part of the Text tools category in the Calabi tools hub. Prefix each line of text with a line number, in your browser. All tools in this category run entirely in your browser with no server involvement.