If you are writing a webpage that accepts email addresses, then please just use <input type="email"> and check for: document.querySelector("[type='email']"

If you are writing a webpage that accepts email addresses, then please just use <input type="email"> and check for: document.querySelector("[type='email']").validity.valid This will not only give you email validation for free, but also gives users with software keyboards (e.g. on phones) a contextual keyboard.