About This Tool
What is Regex Tester?
A tool for testing regular expressions with real-time matching against test strings. Used for debugging and developing regex patterns for string searching, validation, and text parsing in development workflows.
How to Use
- Enter your regex pattern in the top input field.
- Enter the test string in the area below.
- Matching portions are highlighted in real-time.
- Configure flags (case insensitive, multiline, etc.) to adjust matching behavior.
Key Features
- Real-time regex matching with highlighting
- Case insensitive, multiline, and dotAll flags
- Detailed match text, position, and capture group display
- ECMAScript, RE2, and PCRE2 engine selection
Tips
- For email validation, use standardized regex patterns rather than simple ones.
- Capture groups () allow you to extract specific matched portions.
- Using the ? quantifier performs lazy (non-greedy) matching instead of the default greedy matching.
Regex Tester
Test regular expressions with real-time matching
Frequently Asked Questions
Diferença entre .* e .*? ?▼
Greedy (.*) captura o máximo possível. Lazy (.*?) captura o mínimo. Lazy evita matches indesejados.
Testar email com regex?▼
Regex simples de email são imprecisos. Para produção, use bibliotecas de validação dedicadas.
Barras em regex?▼
Delimitadores /.../ são convenção de linguagem, não parte do regex. Use apenas o padrão aqui.
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