Regex Tester

Regular expressions (regex) are powerful pattern-matching sequences used to search, validate, and manipulate text. They are supported in virtually every programming language and text editor. Writing correct regex can be tricky, so a real-time tester lets you experiment with patterns against sample strings and instantly see which parts match, making the development process much faster.

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How to Use

Enter your regex pattern in the pattern field and add optional flags like g (global) or i (case-insensitive). Type or paste your test string below. Matches are highlighted in real time as you type. The tool also shows capture groups and flags any syntax errors in your pattern immediately.

Common Use Cases

• •Validating email addresses, phone numbers, or postal codes
• •Extracting data from structured text like log files or CSV
• •Building search-and-replace patterns for code refactoring
• •Testing input validation rules before adding them to your app
• •Learning and experimenting with regex syntax interactively