Regex Tester
Test regular expressions instantly with live match highlighting. Free online regex tester with flags, explanation, and match details.
What Is a Regex Tester?
A regex tester lets you build and debug regular expressions against real text with instant feedback. Regular expressions (regex) are patterns used to search, match, and extract text — from validating emails to parsing logs and scraping data.
This free regex tool shows you the match count, the position of every match, and supports the standard flags: g (global), i (case-insensitive), and m (multiline).
Common Regex Patterns
Email: \b[\w.-]+@[\w-]+\.[\w.]+\b · Phone: \+?[0-9\s-]{10,15} · URLs: https?:\/\/[\w.-]+ · Dates: \d{4}-\d{2}-\d{2}
Start with simple patterns and build up. The tester updates live, so you can iterate until the pattern matches exactly what you need.
How to Use
- Type your regular expression pattern
- Enter test text to match against
- Toggle flags (g, i, m) as needed
- Read the match count and positions — the pattern updates live
Features
Frequently Asked Questions
\b[\w.-]+@[\w-]+\.[\w.]+\b. It matches most real-world email formats without being overly strict.