How to use Online Regular Expression Builder
- Type or paste your text into Online Regular Expression Builder's input area.
- Set Literal text, Built pattern, Flags so the output fits your use case.
- Select Add literal and the result updates immediately, with no upload.
- When it looks right, Copy pattern to save it.
About this tool
Everything Online Regular Expression Builder does happens on your own device. Online Regular Expression Builder tests your regular expression against sample text in your browser, highlighting matches as you type.
Flags and group captures are surfaced so you can refine the pattern quickly. It behaves the same on desktop and mobile, with nothing stored remotely.
Frequently asked questions
What is Online Regular Expression Builder for?
Use Online Regular Expression Builder to process your input without installing anything using the Literal text, Built pattern controls; everything happens client-side.
Do I need an account for Online Regular Expression Builder?
No — Online Regular Expression Builder needs no account, sign-up or installation.
Is my input private in Online Regular Expression Builder?
Yes — your input never leaves your device; Online Regular Expression Builder does all the work in your browser.
Which regex flavor does Online Regular Expression Builder use?
Online Regular Expression Builder runs your pattern with the browser's own JavaScript regex engine, live and on your device.
Does Online Regular Expression Builder work offline?
Once the page has loaded, Online Regular Expression Builder keeps working with no network connection.