Zadein Logo
Zadein
ToolsPricing
Add to Chrome

Regex Tester

Test regex expressions with real-time highlighting and match detection. Supports JavaScript RegExp syntax.

/
/
Matches will be highlighted here

About the Regex Tester

The Zadein Regex Tester lets you write and test regular expressions against sample text in real time. Matches are highlighted as you type, making it easy to verify and refine patterns before using them in code.

How to use

  1. 1Enter your regular expression in the pattern field.
  2. 2Paste or type the test string in the input area.
  3. 3View highlighted matches and match details instantly.

Common use cases

  • Test a regex pattern for email address validation before adding it to a form.
  • Develop and debug a regular expression for text parsing in a script.
  • Verify that a pattern matches all intended strings and excludes others.
  • Learn regex by experimenting with patterns and seeing results in real time.

Frequently asked questions

Which regex flavour does the tester use?

The tester uses JavaScript regex syntax, which is compatible with most web and scripting environments.

Can I use flags such as case-insensitive or multiline?

Yes. Common flags such as i (case-insensitive), g (global), and m (multiline) can be applied to the pattern.

Does it show all matches or just the first?

With the global flag enabled, all matches in the test string are highlighted. Without it, only the first match is shown.