# Send email with PHP

> Send email from any PHP app with the emailit/emailit-php SDK, plain cURL or PHPMailer over SMTP, and verify Emailit webhook signatures.

This guide covers sending email from a PHP application without a framework: with the official `emailit/emailit-php` SDK, with plain cURL, or over SMTP with PHPMailer. It also shows a webhook endpoint that verifies signatures. Using Laravel? Follow the [Laravel guide](/docs/frameworks/laravel/) instead.

## Prerequisites

- PHP 8.1 or later and Composer.
- A [verified sending domain](/docs/domains/add-a-domain/), for example `acme.com`.
- An [API key](/docs/developers/api-keys/). A Sending Only key restricted to your domain is enough.
- Until your workspace has [production access](/docs/workspaces/production-access/), you can only send to the account emails of workspace members.

## Install the SDK

```bash
composer require emailit/emailit-php
```

The SDK uses Guzzle for HTTP, which Composer installs for you.

## Configure your API key

Set the key as an environment variable in your web server, PHP-FPM pool or hosting panel, and read it at runtime:

```bash
```

```php
$apiKey = getenv('EMAILIT_API_KEY');
```

If you load a `.env` file with a package such as `vlucas/phpdotenv`, keep that file outside the web root and out of version control.

## Send an email

```php title="send.php"
require __DIR__.'/vendor/autoload.php';

$emailit = Emailit::client(getenv('EMAILIT_API_KEY'));

$email = $emailit->emails()->send([
    'from'    => 'Acme <hello@acme.com>',
    'to'      => 'ada@example.com',
    'subject' => 'Your receipt from Acme',
    'html'    => '<p>Thanks for your order.</p>',
    'text'    => 'Thanks for your order.',
]);

echo $email->id; // em_…
```

The same call accepts `cc`, `bcc`, `reply_to`, `attachments`, `template` with `variables`, `scheduled_at` and `tracking`. To attach a file, base64-encode it:

```php
$email = $emailit->emails()->send([
    'from'        => 'Acme Billing <billing@acme.com>',
    'to'          => 'ada@example.com',
    'subject'     => 'Invoice INV-1042',
    'html'        => '<p>Your invoice is attached.</p>',
    'attachments' => [[
        'filename'     => 'INV-1042.pdf',
        'content'      => base64_encode(file_get_contents(__DIR__.'/INV-1042.pdf')),
        'content_type' => 'application/pdf',
    ]],
]);
```

See [Send an email](/docs/api-reference/emails/send/) for every field and [Attachments](/docs/email-api/attachments/) for limits.

### Handle errors

```php
use Emailit\Exceptions\ApiErrorException;
use Emailit\Exceptions\AuthenticationException;
use Emailit\Exceptions\RateLimitException;
use Emailit\Exceptions\UnprocessableEntityException;

try {
    $emailit->emails()->send($message);
} catch (AuthenticationException $e) {
    // 401: the API key is missing or invalid
} catch (RateLimitException $e) {
    // 429: wait and retry
} catch (UnprocessableEntityException $e) {
    // 422: for example, the from domain isn't verified
} catch (ApiErrorException $e) {
    error_log('Emailit error '.$e->getHttpStatus().': '.$e->getMessage());
}
```

## Send without the SDK

If you can't use Composer, call the API with cURL:

```php title="send-curl.php"
$ch = curl_init('https://api.emailit.com/v2/emails');
curl_setopt_array($ch, [
    CURLOPT_POST           => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER     => [
        'Authorization: Bearer '.getenv('EMAILIT_API_KEY'),
        'Content-Type: application/json',
    ],
    CURLOPT_POSTFIELDS     => json_encode([
        'from'    => 'Acme <hello@acme.com>',
        'to'      => 'ada@example.com',
        'subject' => 'Your receipt from Acme',
        'html'    => '<p>Thanks for your order.</p>',
    ]),
]);

$body = curl_exec($ch);
$status = curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
curl_close($ch);

if ($status >= 400) {
    throw new RuntimeException("Emailit returned $status: $body");
}

$email = json_decode($body, true); // $email['id'] is the em_ ID
```

## Send with SMTP instead

Any PHP mail library that supports SMTP works. With [PHPMailer](https://github.com/PHPMailer/PHPMailer) (`composer require phpmailer/phpmailer`):

```php title="send-smtp.php"
use PHPMailer\PHPMailer\PHPMailer;

require __DIR__.'/vendor/autoload.php';

$mail = new PHPMailer(true);
$mail->isSMTP();
$mail->Host       = 'smtp.emailit.com';
$mail->Port       = 587;
$mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
$mail->SMTPAuth   = true;
$mail->Username   = 'emailit';
$mail->Password   = getenv('EMAILIT_API_KEY');

$mail->setFrom('hello@acme.com', 'Acme');
$mail->addAddress('ada@example.com');
$mail->Subject = 'Your receipt from Acme';
$mail->isHTML(true);
$mail->Body    = '<p>Thanks for your order.</p>';
$mail->AltBody = 'Thanks for your order.';

$mail->send();
```

With Symfony Mailer, use the DSN `smtp://emailit:API_KEY@smtp.emailit.com:587`. For implicit TLS use port 465 (`PHPMailer::ENCRYPTION_SMTPS`); if your host blocks 587, try 2525 or 2587. See [SMTP settings](/docs/smtp/settings/).

## Receive webhooks

[Create a webhook](/docs/webhooks/set-up/) that points to your endpoint and store its signing secret in `EMAILIT_WEBHOOK_SECRET`. Read the raw body from `php://input` and verify it before you trust it:

```php title="webhook.php"
$payload   = file_get_contents('php://input');
$signature = $_SERVER['HTTP_X_EMAILIT_SIGNATURE'] ?? '';
$timestamp = $_SERVER['HTTP_X_EMAILIT_TIMESTAMP'] ?? '';
$secret    = getenv('EMAILIT_WEBHOOK_SECRET');

$expected = hash_hmac('sha256', $timestamp.'.'.$payload, $secret);

if (abs(time() - (int) $timestamp) > 300 || ! hash_equals($expected, $signature)) {
    http_response_code(401);
    exit('Invalid signature');
}

// The body is a JSON array of up to 100 events.
foreach (json_decode($payload, true) as $event) {
    if ($event['type'] === 'email.bounced') {
        $address = $event['data']['object']['to'];
        // Stop emailing $address.
    }
}

http_response_code(200);
```

Respond within 30 seconds with a `2xx`; anything else is retried. See [Request signature](/docs/webhooks/request-signature/).

## Production tips

- **Reuse one client** per request or worker instead of creating one per email.
- **Send in the background.** For bulk sends, push messages onto a queue and send from a worker, so pages stay fast and you stay under your [sending limits](/docs/limits/) (2 emails per second by default).
- **Make retries safe.** If you retry after a timeout, send an `Idempotency-Key` header with cURL so the email isn't sent twice. See [Idempotency](/docs/email-api/idempotency/).
- **Keep keys out of the web root.** Never commit keys or `.env` files, and use a separate key per app.

## Next steps

  - [Laravel](/docs/frameworks/laravel/): Mail transport and facade for Laravel apps.
  - [WordPress](/docs/frameworks/wordpress/): Route WordPress mail through Emailit SMTP.
  - [Send email with the API](/docs/email-api/send-email/): Templates, scheduling and tracking.
  - [Webhook event types](/docs/webhooks/event-types/): Every event and its payload.

---
Source: https://emailit.com/docs/frameworks/php/