Developer Tools
Regex Tester
Test regular expressions against sample text instantly. Supports ignore case, multiline, and dotall flags. Free online regex tester.
Input
Result
Matches will appear here.
How to Use
- Type a regular expression pattern, such as
\d+. - Optionally check i (ignore case), m (multiline), or s (dot matches newline).
- Paste the text you want to test against the pattern.
- 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.
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