Test JavaScript regex with live highlighting. See railroad diagrams. Free, no signup.
[\w.+-]+@[\w-]+\.[\w.-]+
https?://[\w.-]+
\d{3}-\d{3}-\d{4}
\d{4}-\d{2}-\d{2}
\b\d{1,3}(\.\d{1,3}){3}\b
<(\w+).*?>