Developer Tools

Regular Expression Tester & Matcher

Test and validate regular expressions with live matching and detailed match information.

Part of Yoopla's 445+ free browser tools.

Regular Expression Pattern

Test String

Common Regex Patterns:

^\d{3}-\d{3}-\d{4}$Phone number

^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$Email

^https?://URL

#[0-9A-Fa-f]{6}Hex color

\b[A-Z]{2,}\bAcronyms

\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}IP address

How to Use Regex Tester

1
Enter your regular expression pattern in the pattern field.
2
Choose flags (g for global, i for case-insensitive, etc.).
3
Enter or paste your test string.
4
See matches highlighted in real-time with match details.

Frequently Asked Questions

What are regex flags?▾

Flags modify how the pattern matching works: g (global) finds all matches, i (case insensitive) ignores case, m (multiline) treats ^ and $ as line boundaries.

How do I see capture groups?▾

Use parentheses () in your pattern to create groups. The tool shows all captured groups for each match.

Which regex syntax is supported?▾

The tool uses JavaScript regular expressions, which support most common syntax including lookaheads, lookbehinds, named groups, and character classes.

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