Regex Tester
Test and debug regular expressions
//
Results will appear here...
What is a Regex Tester?
Regular Expressions (Regex) are powerful patterns used to match character combinations in strings. This tester provides a real-time playground to write, debug, and understand your regex patterns against test data.
Regex is used everywhere: validation (email, phone numbers), search/replace operations, and data parsing. However, writing them can be cryptic and error-prone.
Our tool visualizes matches instantly. It highlights precisely what your pattern is catching, helping you spot mistakes like 'greedy' matching or incorrect group captures.
1How to Use
- Write Pattern: Enter your regex in the top bar (e.g., `\d+` for numbers).
- Set Flags: Add flags like `g` (global) or `i` (case-insensitive) in the small box.
- Add Test Data: Paste text into the 'Test String' area.
- Analyze Matches: Watch the text light up where it matches.
- Inspect Groups: (Coming soon) Check which parts of the string were captured by parentheses.
★Key Features
- Live Highlighting: Matches appear in yellow as you type.
- JavaScript Engine: Uses your browser's native JS RegExp engine for 100% accuracy.
- Error Reporting: Shows syntax errors immediately (e.g., unclosed brackets).
- Flag Support: Full support for standard flags (g, i, m, s, u, y).
- Zero Latency: No server round-trips; everything happens locally.