Add a Prefix to a String
Prepend text to a string (or to every line of it). Runs entirely in your browser, so your data never leaves your device.
0 chars · 0 lines
Output
The result appears here as you type.
How to use Add a Prefix to a String
- 1. Paste the text to prefix. Enter the string or multi-line block you want text added to the front of. A single word and a whole file's worth of lines both work.
- 2. Enter the prefix. Type the exact characters to prepend, such as a quote marker, indent, or tag. Turn on Add to every line to apply it at the start of each line instead of only the first.
- 3. Copy the prefixed result. Copy the output and paste it into your document, email quote, or code file wherever the prefixed text belongs.
When to use Add a Prefix to a String
Add a Prefix to a String prepends a chosen piece of text either once, at the very start, or repeatedly at the start of every line. It handles the tedious version of a task that manual editing makes error-prone across many lines.
- Quoting an email reply. You are replying to a long email thread and want to prefix every line of the quoted message with '> ', the same convention plain-text mail clients use for blockquotes.
- Commenting out a config block. A YAML or shell config file needs every line temporarily disabled by prepending a '#' comment marker, without opening the file in an editor to do it by hand.
- Labeling log lines by source. You are merging log output from two services and want to prefix each line from one source with a short tag like '[api]' before combining them for easier scanning.
- Building CLI flag lists. You have a list of filenames and need each one prefixed with '--include=' to build a long command-line argument string for a build tool or linter.
Examples
Quote every line
Input
one two
Output
> one > two
About the Add a Prefix to a String tool
Add a Prefix to a String is a free online tool that works entirely inside your web browser. Prepend text to a string (or to every line of it). Because the processing happens on your own device, nothing you enter is uploaded, logged or stored anywhere.
This page is one of 159 String utilities on EditSafely. Each one does a single job well, and all of them follow the same rule: your input stays on your machine.
You can shape the output with 2 settings, including Prefix and Add to every line, and the result refreshes the moment you change one. A worked example further down the page shows exactly what the tool produces for a real input.
Because nothing leaves your device, the tool is suitable for sensitive content such as internal documents, credentials or customer data. It also responds instantly, since every keystroke is handled on your own machine rather than by a remote API.
Frequently asked questions
Is Add a Prefix to a String free to use?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Is it safe to paste sensitive or confidential data?
Everything happens locally. Your browser downloads the tool's code once, then does all the processing itself; nothing you enter is transmitted, stored or logged. You can even go offline after the page loads and it will still work.
How much text can I process at once?
There is no fixed limit. Because the work happens on your own device rather than on a shared server, the practical ceiling is your machine's memory, which comfortably handles inputs far larger than typical online tools allow.
Do I need to sign up or install anything?
No. The tool works in any modern browser on desktop, tablet or phone. There is no account to create, no extension to add and no software to install.
How do I use the result?
The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.