Mailchimp API Add Subscriber – Code Examples

Previously I did a lot of work with Mailchimp API in PHP while creating my Mailchimp and WordPress sync plugin, so why not share some working and ready code example with you guys.

In this tutorial examples I am going to use PHP and cURL in order to connect to Mailchimp API. I have a tutorial with WordPress examples as well.

The long story short, here is the ready to use code.

// let's start with some variables
$api_key = 'YOUR MAILCHIMP API KEY HERE';
$email = 'no-reply@rudrastyh.com'; // the user we are going to subscribe
$status = 'subscribed'; // we are going to talk about it in just a little bit
$merge_fields = array( 'FNAME' => 'Misha' ); // FNAME, LNAME or something else
$list_id = ''; // List / Audience ID

// start our Mailchimp connection
$connection = curl_init();
curl_setopt( 
	$connection, 
	CURLOPT_URL, 
	'https://' . substr( $api_key, strpos( $api_key, '-' ) + 1 ) . '.api.mailchimp.com/3.0/lists/' . $list_id . '/members/' . md5( strtolower( $email ) )
);
curl_setopt( $connection, CURLOPT_HTTPHEADER, array( 'Content-Type: application/json', 'Authorization: Basic '. base64_encode( 'user:'.$api_key ) ) );
curl_setopt( $connection, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $connection, CURLOPT_CUSTOMREQUEST, 'PUT' );
curl_setopt( $connection, CURLOPT_POST, true );
curl_setopt( $connection, CURLOPT_SSL_VERIFYPEER, false );
curl_setopt( 
	$connection, 
	CURLOPT_POSTFIELDS, 
	json_encode( array(
		'apikey'        => $api_key,
		'email_address' => $email,
		'status'        => $status,
		'merge_fields'  => $merge_fields,
		//'tags' => array( 'Coffee', 'Snowboard' ) // you can specify some tags here as well
	) )
);
 
$result = curl_exec( $connection );

Let’s break down this whole code example into small parts and describe every of them.

• On line 4 we used subscribed status because we are going to subscribe a user. If your goal is to unsubscribe this specific user using Mailchimp API, you can change the status to unsubscribed. Or pending if it is required to send a confirmation email.
• $result is a JSON object, so in order to process the result from the API, you have to json_decode() it first, example print_r( json_decode( $results ) ).
• You might also notice that API key is used as a part of URL and for basic auth.
• How to get an API key and Audience ID we will talk in just a little bit.

$result = json_decode( $result );

if( 400 === $result->status ){
	foreach( $result->errors as $error ) {
		echo '<p>Error: ' . $error->message . '</p>';
	}
} elseif( 'subscribed' === $result->status ){
	echo "<p>Thank you, {$result->full_name}!</p>";
}

Get Mailchimp API key

The very first lines of our code require us to specify Mailchimp API key. I am more than sure that you know how to get it, but just in case I will remind you.

Sign-in into your Mailchimp dashboard and click on your photo in the bottom left part of the screen. Then – Account & Billing.

Then, in Account & billing page please go to Extras – API keys.

Everything else should be intuitively simple, I am sure you will figure it out.

Find out your Audience ID (former List ID)

Login to Mailchimp, go to Audiences (Lists) then click on the list title, then in list menu Settings > List name and defaults.

# Mailchimp

Misha Rudrastyh

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