GuidesGetting Started with the Email Validation API

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The Email Validation API allows you to validate a list of email addresses and to retrieve detailed validation results.

Getting started

Start with a simple validate query for a list of email addresses. Use the API key from your account.

curl --request POST \
 --url '' \
 --header 'Authorization: Bearer <<your API key>>' \
 --data '{ "emails": [""] }'

This validates a single email address and returns the result.


The Email Validation API returns a result object for each email address in the request.

    "results": [
            "email": "",
            "result": {
                "syntax": "pass",
                "mx": "pass",
                "mailbox": "fail",
                "score": 0,
                "description": [

Can I use the email address?

If the score is greater than 2 you can use the email address and emails will most likely not bounce.

A score of 2 identifies email addresses that will be delivered, but the email address is a SPAM Trap or temporary email address.  


Element Values Description
syntax pass, fail Email syntax check result.
mx pass, fail MX record lookup result. Checks if the domain exists and publishes information about an email server
mailbox pass, fail, n/a Mailbox check result. Checks if the email server can be reached and tries to verify if the email address exists. Returns n/a if the mailbox cannot be verified.


The score range goes from 0 to 10 where 0 identifies an email that is guaranteed to not be usable and 10 means that all checks passed and emails will be delivered to a personal email address.

Score Description
0 Email will bounce
2 Email can be used, but looks like a SPAM Trap or temporary email address.
9 Email looks good, but mailbox couldn't be verified.
10 Email address passed all checks and emails will be accepted by the server.


The description contains additional information about the check results and resulting score.

Value Description
syntax Email syntax check failed.
domain Domain doesn't exist or no MX record configured.
mailbox Mailbox check returned unknown recipient.
verifyRejected Mailbox could not be verified. The recipient's mail server rejected verification attempts
blacklist Email address has been detected in local blacklist
disposable Email address or domain has been detected as temporary email address.
catchall Email address has been identified as a common catch all address.


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