Regex

Write a regular expression and see matches highlighted in your test text immediately. Great for debugging patterns before putting them into code.

How to use

1. Enter the regular expression and flags (g, i, m…)
2. Paste the test text below
3. Matches highlight live as you edit either field

Frequently asked questions

Which regex flavor is used?

JavaScript (ECMAScript) — the same engine as in browsers and Node.js. Most patterns are portable to Python/Java with minor changes.

What do the flags mean?

g finds all matches instead of the first, i ignores case, m makes ^ and $ match at line boundaries.

Why does my pattern match too much?

Quantifiers are greedy by default: .* grabs as much as possible. Add ? for a lazy version (.*?) or restrict the character class.

Is the text sent anywhere?

No — matching runs in your browser.