Regex Tester
Test JavaScript regular expressions, highlight matches and inspect matched values instantly.
Online Regular Expression Tester
Regex Tester helps you experiment with regular expressions and check how a pattern matches text. Regular expressions, commonly called regex, are used in programming, data processing, validation, search operations, and text manipulation. Because regex patterns can become complex, testing them before adding them to a project can save time.
How to Test a Regex Pattern
Enter a regular expression in the pattern field and provide sample text to test against it. The tool can help you see whether the expression matches the expected parts of the text. You can adjust the pattern and test again until it produces the result you need.
Common Uses for Regular Expressions
Regex can be useful for finding text patterns, extracting information, checking input formats, replacing text, and processing structured strings. Developers often use regular expressions when working with logs, forms, configuration files, source code, and datasets.
Test Before Using in Production
Testing a pattern with representative sample data can help reveal unexpected matches or missing cases. Keep in mind that regular expression behavior can differ between programming languages and regex engines, so a pattern should also be verified in the environment where it will ultimately be used.