With the CaptainVerify API, you can integrate email verification into your own applications. We recommend using the API afterwards because a verification can be more or less long (1 or 2 minutes) so it is better to avoid plugging it into your form directly because you risk losing leads.

API key

An account is required to generate the key for the API, this will give you access to the service.

The request

To make a request to the API, simply call the GET protocol at this URL:


Replace john.doe@gmail.com with your email to verify

API Limits

The API is limited to a maximum of 2 simultaneous connections and 50 checks per minute. When integrating the API, make sure that your application does not exceed this limit.

The answer

A json table will be returned with these variables:

Variables Possible value


true, false
If authentication has failed, the exhaustion of your credits


default : null
When the success is false, an error message will be sent.


Credits available on your account


The email you want to check


Email standardized, elimination of labels for gmail ... support+test@gmail.com will be support@gmail.com


true, false
If the email user has a role, eg support@example.com


true, false
If the email provider is free, ex: Gmail.com


true, false
The email is valid, but disposable after a short period it will no longer be possible to contact the user.


true, false
If the email provider is fighting spam and is not a real user


default : null
If for example, the email is john.doe@gmil.com, the API will send you a proposal like john.doe@gmail.com


valid, invalid, unknown
The status of the email. if all your credits have been used up, the unknown status will always be returned, so as not to block your application.


null, error, smtp_error, antispam_system, email_disable, ok_for_all...
Understand why an audit is unknown.

To check the validity of your emails with our API. Register Now