Every invalid email address quietly erodes your business — bounced order confirmations, failed password resets, wasted marketing spend and, worst of all, damage to your sender reputation that pushes future mail into spam folders. AutoPostcode validates addresses at the moment of capture so only real, reachable inboxes make it into your database.
See it in action
Watch the API check syntax and MX records, suggest fixes for typos, and reject inboxes that would bounce.
Typo caught & corrected
Deliverable, with a suggested fix
Undeliverable domain
No MX record → reject at signup
What the API checks
- Syntax and RFC formatting
- Domain existence and valid MX records
- Disposable / throwaway address detection
- Role-based inbox detection (info@, admin@)
- Catch-all and mailbox deliverability signals
- Typo detection with suggested corrections
A clear, actionable verdict
Every response returns one of four verdicts so your logic stays simple:
- valid — safe to accept and send to
- invalid — bad syntax or non-existent domain; reject it
- risky — deliverable but low-confidence (catch-all, role-based, disposable); warn or gate
- unknown — the mail server could not be verified in time; accept with caution
Example response
{
"email": "jane@example.com",
"verdict": "valid", // valid | invalid | risky | unknown
"result": "valid",
"flags": [],
"suggested_correction": null
}Catching typos before they cost you
When someone types jane@gmial.com, the API returns suggested_correction: "jane@gmail.com". Surface that inline and you recover a customer who would otherwise never get their confirmation email.
Where teams use it
- Validating email at sign-up and checkout to protect deliverability
- Cleaning existing lists before a campaign to cut bounce rates
- Blocking disposable addresses on free trials and promotions
- Reducing fraud and fake accounts at registration
One API key for every check
Email validation shares a single API key and credit pool with postcode lookup, phone validation and bank account validation — clean data across your whole stack from one integration.
Frequently asked questions
What does the email validation API check?
Syntax, domain existence, MX records, disposable and role-based addresses, and mailbox-level deliverability signals. It returns a verdict of valid, invalid, risky or unknown, plus a suggested correction for obvious typos like gmial.com.
Can it catch typos?
Yes. When an address looks like a near-miss of a common provider (for example jane@gmial.com), the API returns a suggested_correction so you can prompt the user to fix it before they submit.
What is a 'risky' verdict?
Risky means the address is syntactically valid and the domain accepts mail, but there are signals that lower deliverability confidence — such as catch-all domains, role-based inboxes (info@, sales@) or disposable providers. You decide whether to accept, warn or block.
How much does email validation cost?
1 credit per check, drawn from the same shared credit pool as postcode lookup, phone and bank validation — one API key covers everything.
Ready to get started?
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