Regex Tester

How to Use

1. Type a regular expression pattern, such as \d+.
2. Optionally check i (ignore case), m (multiline), or s (dot matches newline).
3. Paste the text you want to test against the pattern.
4. Matches, their positions, and capture groups are highlighted automatically.

About Regular Expressions

A regular expression (regex) is a pattern language for matching text. Special characters like \d (digit), \w (word character), + (one or more), and * (zero or more) let you describe complex search patterns in a single line. This tool uses Python's re module, which follows the widely used PCRE-style syntax shared by most modern programming languages.

Common Uses

• Validating input formats like email addresses or phone numbers before writing code.
• Testing a pattern used in a script or configuration file (e.g. nginx, logstash).
• Extracting specific substrings (capture groups) from log lines or text data.