Regex Editor & Tester

This regex matches standard email address formats with basic validation. It requires the local part to start with an alphanumeric character and allows hyphens and underscores in between. The domain part permits multiple subdomains with optional dots and hyphens, followed by a TLD of 2-3 characters with an optional country code suffix (like .uk or .au). It's case-insensitive due to the 'i' flag.