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
Perbedaan .* dan .*? ?▼
Greedy (.*) mencocokkan sebanyak mungkin. Lazy (.*?) mencocokkan sesedikit mungkin.
Validasi email dengan regex?▼
Regex email sederhana tidak akurat. Untuk produksi, gunakan library validasi khusus.
Garis miring di regex?▼
Delimiter /.../ adalah konvensi bahasa, bukan bagian regex. Gunakan hanya polanya di sini.
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