Question 1

How do I test a regular expression online?

Accepted Answer

Enter your regex pattern in the pattern field and your test string in the text area below. Matches are highlighted in real-time. You can see match details including captured groups in the results panel.

Question 2

What regex flags are supported?

Accepted Answer

This tester supports all JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), and u (unicode). Toggle them using the flag checkboxes.

Pattern	Description
`[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z]{2,}`	Email address
`https?://[^\s/$.?#].[^\s]*`	URL
`\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b`	IPv4 address
`\d{4}-\d{2}-\d{2}`	Date (YYYY-MM-DD)
`^(?=.[a-z])(?=.[A-Z])(?=.*\d).{8,}$`	Strong password
`#?([0-9A-Fa-f]{3}\|[0-9A-Fa-f]{6})\b`	HEX color

Regex Tester

Common Patterns

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