API method POST /v1/send

With this method you can send an email. There are several variables, that you should set as email data in your POST request:

General data

Recipient and envelope

The most important and mandatory variable is the "recipient" variable. This variable controls where the email is delivered and should therefore contain an email address. Note that this email address should be pure. This means it should just contain the email address without the name of the recipient or angle brackets ('<' and '>') (i.e. it should state richard@copernica.com and not "Richard" <richard@copernica.com>).

If you want to send the same email to multiple email addresses you can do so by setting "recipients" to an array of email addresses instead of one single address.

Another important variable, although not mandatory, is the "envelope" variable. If delivery fails, the email address given here will receive a delivery status notification indicating the failure and the reason why. If this variable is not included, the bounces are not sent back to you, but are processed by ResponsiveEmail.com and used for statistics.

The recipient and envelope variables control where the email is delivered ('recipient') and where delivery failure notifications are sent to ('envelope'). They are like the addresses written on the outside of an envelope, they do not influence the way the actual letter (email), looks.


ResponsiveEmail also offers the following boolean variables (e.g. "variable": true/false), which can be included in each POST request. Using these variables you can enable or disable certain features. This makes it possible to use different settings for individual emails.

"inlinecss":           When set to true, all CSS will be inlined inside the HTML
"trackclicks":         When set to true, links will be redirected and tracked
"trackbounces":        When set to true, bounces will be tracked
"trackopens":          When set to true, opens will be tracked

These variables are optional and enabled by default, omitting a variable means it will automatically be set to 'true'.


If you have included an envelope address, you can further finetune what kind of status notifications you like to receive with the "dsn" property. It supports the following properties:

"notify":           either "NEVER" or one or more of "FAILURE", "SUCCESS" and "DELAY", comma-separated
"orcpt":            The original recipient (defaults to the recipient address)
"ret":              Either "FULL" to receive the full message back or "HDRS" to receive just the headers
"envid":            Original-envelope-id to be included in the bounce message

Sending MIME data

The "send" method can both be used to send fully formatted MIME messages, or to send many different fields so that ResponsiveEmail can generate the MIME message for you. If you create the MIME message yourself, you need to provide at least "recipient" and "mime" variables.

Sending non-MIME data

If the "mime" field is not included in the call to the REST API, ResponsiveEmail will generate an email based on the settings of the following variables:

From, to and cc

You may have noticed that we specify variables, such as "from" and "to" here. These might seem redundant, because we have already specified the "recipient" and "envelope" addresses. However, these variables do not control the actual delivery, but only the way the MIME looks. They same is valid for the "cc" variable. Whereas "envelope" and "recipient" can be seen as the outside of an envelope, "from" and "to" can be seen as the address details that are put on the letter itself. The "cc" variable has to be a string or array containing the cc email addresses.

Subject, text and HTML

You can usespecify the "subject", "text" and "html" properties to set the subject, and the HTML and text version of the mail.

Example request

In the example below we've used JSON to format the entire email. You can of course also submit already formatted MIME messages via the REST API and the "mime" variable.

POST /v1/send?access_token=yourtoken
Host: www.responsiveemail.com
Content-Type: application/json

    "envelope": "example@example.org",
    "recipient": "john@doe.com",
    "subject":  "This is the subject",
    "html": "<html><head><style>body { font-weight: 600; }</style></head><body>Hello there!</body></html>",
    "text": "This is example content text",
    "from" : "example@example.org",
    "to": "john@doe.com",
    "cc": "john@doedoe.com",
    "inlinecss": true,
    "trackclicks": false,
    "trackbounces": true,
    "trackopens": false,
    "dsn": {
        "notify": "SUCCESS",
        "orcpt": "john@doe.com",
        "ret":  "HDRS",

## Return data

After successfully posting your request, your message or messages will be sent.
Each sent message will get a unique ID to identify it. These unique IDs will
be returned to you as properties in a JSON encoded string. The value of each
property is the recipient of the message. The JSON looks like:

    "id1" : "recipient1",
    "id2" : "recipient2",

Personalizing emails

It is possible to add data to your JSON that later on is used to personalize your email. If you send a JSON with only one recipient, you can add a property "data" to your JSON holding a JSON object:

    "data" :{
        "firstname": "John",
        "lastname": "Doe"

If you send a mail with multiple recipients, the data can be passed in the recipients property as follows:

    "recipients" : [
        "jane@doe.com": {
            "firsname": "Jane",
            "familyname": "Doe"
        "john@doe.com": {
            "firstname": "John",
            "familyname": "Doe"

Found a typo?

You can find this documentation page on GitHub.
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