Check that the email has one `@` symbol
Check that there is text before and after the `@`
Check that the domain part contains at least one `.` after the `@`
Check that the domain does not start or end with a dot
Check that there are no spaces in the email address
Check that the local part and domain part use allowed characters only
Check that the top-level domain is present and valid
Use a regular expression to validate the email format
Send a confirmation email with a verification link or code
Check the email against DNS MX records for the domain
Use an email validation API or service
Remove temporary, disposable, and role-based addresses if needed