Test Regular Expressions Online for Free

The Regex Tester allows you to validate and debug your regular expressions against sample text strings in real time — perfect for developers building complex search patterns or data validators. It highlights matches instantly and provides feedback so you can refine your patterns without leaving the browser. Completely free, private, and requires no account or registration.

1. 1

   Enter your regular expression in the pattern field at the top.

2. 2

   Type or paste your test string in the text area below.

3. 3

   Matches are highlighted in real time as you type — hover any match to see its captured groups.

4. 4

   Enter your regular expression pattern and flags.

5. 5

   Paste your test string into the text field below.

6. 6

   Review the highlighted matches to verify your regex logic.

7. 7

   What is a regular expression used for?

8. 8

   Regular expressions (Regex) are used to search, validate, and manipulate text strings based on specific patterns, such as email or phone number validation.