What regex features are supported?

Our tool supports most JavaScript regex features including flags (g, i, m, s, u), groups, lookaheads, and more.

Regex Tester — Test & Debug Regular Expressions Online

Q: Is the regex tester free?

Yes, ToolifyX regex tester is completely free to use. No registration, no credit card, and no hidden fees.

Regex Tester

Enter regex pattern and test text below

Pattern g i m

Replacement (optional) 0 matches

Test Text Characters: 0

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Regex Tester — Test & Debug Regular Expressions Online Free

What is a Regular Expression?

A regular expression (regex) is a sequence of characters that specifies a search pattern. Used for text search, validation, parsing, and replacement, regex is an essential tool for developers, data analysts, and system administrators.

How to Use

Enter your regex pattern in the pattern field
Enter test text to test the pattern against
Click Test Regex to see all matches highlighted
Use Replace to replace matches with replacement text

Supported Regex Features

Standard JavaScript regex syntax
Flags: global (g), ignore case (i), multiline (m)
Capture groups and lookaheads
Real-time match highlighting

Frequently Asked Questions

Is the regex tester free?

Yes, completely free. No signup, no credit card, no hidden fees.

What regex flavors are supported?

Our tool uses JavaScript regex syntax, which supports most common patterns including groups, lookaheads, and flags.

Is my regex data secure?

Absolutely. All processing happens locally in your browser. Your regex and test data never leave your device.