🔍 Regex Tester

Common Regex Patterns

Click a pattern to use it:

About Regex Tester

Regular expressions (regex) are powerful patterns used to match character combinations in strings. Our regex tester provides real-time feedback as you type, highlighting all matches in your test string.

Common Flags:

• g (global): Find all matches, not just the first
• i (case-insensitive): Ignore case when matching
• m (multiline): ^ and $ match start/end of each line
• s (dotall): Dot (.) matches newlines

Common Use Cases:

• Form Validation: Validate email, phone, URL inputs
• Data Extraction: Extract specific patterns from text
• Search & Replace: Find and replace text using patterns
• Log Parsing: Parse structured log files

Frequently Asked Questions

What is a regular expression?

A regular expression (regex) is a sequence of characters that defines a search pattern. It's used for pattern matching within strings — useful for validation, extraction, and text processing.

How do I use this tool?

Enter your regex pattern in the first field, set the flags (g, i, m), then type or paste your test string. Matches will be highlighted automatically.

What language is this regex for?

This tool uses JavaScript regex syntax, which is very similar to most modern programming languages (Python, Java, PHP, etc.).

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