html email regex

<input name="email" type="email" pattern="[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{1,63}$" class="form-control" placeholder="Email*" id="email" required="">

var email = /^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$/;