Regex Tester

Test regular expressions against sample text.

Regex Tester runs a JavaScript regular expression against multiline sample text and lists matches with indexes.

Input

Output

When to use Regex Tester

Prototyping validation patterns
Checking capture behavior quickly
Teaching regex flags like g and i

Example

/hello/gi
Hello HTML
Say hello again

Benefits

Free to use—no account required
Runs in your browser
Instant results with no software install
Basic processing does not upload your content to a server
Invalid patterns throw. Keep the first line as a literal /.../flags form.

Not the same as

This is not a replace tool—it reports matches for inspection.

Related tools