Regex Tester

What is Regex Testing?

Regular expressions (regex) are patterns used to match character combinations in strings. They are powerful tools for searching, extracting, and validating text. However, writing correct regex can be challenging, especially for complex patterns. This tool helps you test and debug your regular expressions in real time.

Enter your regex pattern, choose flags, and paste test text to see matches highlighted. The tool also shows match counts, capture groups, and detailed information about each match.

All processing is done locally in your browser – your data never leaves your device.

How to Use

Step 1: Enter your regular expression pattern (without delimiters) in the pattern field.
Step 2: Select regex flags: Global (g), Case Insensitive (i), Multiline (m).
Step 3: Paste or type the text you want to test against.
Step 4: Click "Test Regex" to see matches highlighted and match details.
Step 5: Copy the results using the "Copy Result" button.

The tool supports JavaScript regex syntax, including capture groups, character classes, quantifiers, and lookaheads.

Examples

Email regex: \b[\w.-]+@[\w.-]+\.\w+\b
Phone number: \d{3}[-.]?\d{3}[-.]?\d{4}
URL: https?://[^\s]+

Who Uses Regex Testers?

• Web Developers – validating form inputs.
• Data Engineers – extracting patterns from text.
• Security Analysts – detecting malicious patterns.
• System Administrators – parsing log files.
• QA Engineers – testing text validation.

Pro Tips

• Use the global flag (g) to find all matches, not just the first one.
• Test regex on sample data that represents real‑world input.
• Capture groups help you extract specific parts of a match.
• Start with simple patterns and gradually add complexity.
• Use online regex resources to learn syntax and common patterns.

Frequently Asked Questions