Sending & delivery events
Email validation
Checking whether an email address is correctly formatted, belongs to a domain that accepts mail, and isn’t disposable, before you add it to a list or send to it.
What validation checks
- Format: is it a correctly formed email address?
- Domain: does the domain exist, and does it have MX records so it can receive mail?
- Disposable addresses: is it from a throwaway inbox service that will be gone tomorrow?
Where to validate
Validate at the point of entry: signup forms, checkout and imports. Catching a typo while the person is still on the page lets them fix it, and stops a bad address from ever becoming a bounce.
Email validation in MailCraft
MailCraft’s validation endpoint checks format, MX records and disposable domains in a single call, without sending anything, so you can use it in signup forms and imports.
Let MailCraft handle the details
Authentication, bounces, complaints and suppression are built in. Start free with 3,000 emails a month, no credit card required.
Start freeRelated terms
Full glossarySending & delivery events
Hard bounce
A permanent delivery failure — the address or domain doesn’t exist. Hard bounces should be suppressed immediately and never retried.
Deliverability
Spam trap
An email address with no real owner, used by mailbox providers and blocklists to catch senders with poor list hygiene — sending to one is a strong negative signal.
Deliverability
List hygiene
The ongoing work of keeping your contact list accurate and engaged: removing invalid addresses, bounces and long-inactive contacts so you only send to people who can and want to receive your mail.