Regex Tester

Test and debug regular expressions in real-time. See matches highlighted with capture groups and explanations.

100% PrivateInstantAny Device

Regular Expression

//g

Flags

g (global)i (case-insensitive)m (multiline)s (dotAll)

Test String

0 matches found

Quick Patterns

How to Test Regex

Test and debug regular expressions with live matching.

Enter Pattern

Type your regex pattern.

Add Test Text

Paste text to match against.

See Matches

View highlighted matches live.

Refine Pattern

Adjust your regex until it works.

Why Use Our Regex Tester?

Debug and perfect regular expressions.

Live Matching

See matches as you type.

100% Private

No data leaves your browser.

Flag Support

Global, case-insensitive, multiline flags.

Any Device

Works everywhere.

Match Export

Copy matched results.

No Sign-Up

No account needed.

Common Use Cases

See how regex testing is used.

Email Validation

Input

Pattern: [\w.]+@[\w.]+
Text: user@example.com

Output

Match: user@example.com

Phone Numbers

Input

Pattern: \d{3}-\d{4}
Text: Call 555-1234

Output

Match: 555-1234

URLs

Input

Pattern: https?://\S+
Text: Visit https://site.com

Output

Match: https://site.com

Dates

Input

Pattern: \d{4}-\d{2}-\d{2}
Text: Date: 2024-01-15

Output

Match: 2024-01-15

Frequently Asked Questions

As you type your pattern and test string, the tool instantly compiles the regex and runs it against the test string. Matches are highlighted in-place and listed below with their positions and capture groups.

Flags modify how the regex engine behaves: g (global) finds all matches, i (case-insensitive) ignores case, m (multiline) makes ^ and $ match line starts/ends, s (dotAll) makes . match newlines.

Capture groups are parts of the regex enclosed in parentheses (). They let you extract specific portions of a match. Named groups use (?<name>...) syntax.

The tool gracefully catches regex compilation errors and displays a descriptive error message so you can fix the pattern.

Yes. All regex testing happens locally in your browser — no data is sent to any server.

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