• The most important best practice to follow is this: don’t try and verify on every keypress. If you do, the customer won’t even be able to finish typing their email address before their IP burns out and they can’t verify anything. The best bet is to verify onChange or onBlur or even onSubmit.
• It can make sense to ‘hoist’ the email field higher up in your form so that, while the verification is executing, the user can be filling out the rest of the form. However, we do aim to return responses in extremely quickly - but in some circumstances it can take up to a few seconds. You’ll want to give your users the rest of your form to fill out while it’s verifying.
• Don’t try to do anything sneaky or weird. Number one, it probably won’t work - and number two, If you do, you’re going to find that your IP gets blocked, and then you’re gonna have a hard time.