Test Python regular expression patterns online. Get real-time match results, capture groups, and position info to quickly debug text processing rules.
re.I / i
re.M / m
re.S / s
re.X
re.A
Enter both a regex pattern and input text
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When writing regular expressions in Python, do you often find yourself repeatedly debugging due to escaping errors or unexpected match results? This tool directly simulates the matching engine of the Python re module. After entering your regex pattern and test text, it returns structured results in real time, including all matches, capture group contents, and start/end positions. Regular expressions are string templates used for text pattern matching and extraction, defining match patterns through syntax rules like metacharacters, quantifiers, and grouping.
Q: How do I handle backslash escaping in Python regex?
A: Always use the raw string prefix r''. For example, r'\d+' correctly matches digits, preventing Python from escaping \d into a normal character.
Q: How can I extract the last eight digits of a phone number from a string?
A: Use the group capture pattern r'(\d{3})-(\d{4})-(\d{4})' and check the contents of the second and third capture groups in the results.
Avoid using complex regular expressions on extremely long text (over 10,000 characters) as it may cause performance issues. This tool does not save user-inputted text data, but we still advise against processing sensitive information. Be aware of the default greedy matching behavior of regex; for non-greedy matching, add a ? after the quantifier.
For better performance, it is recommended to precompile complex regex patterns using re.compile. For phone number matching, the recommended pattern r'(?
