# Webhooks

Webhooks allow you to subscribe to real-time notifications about various events that occur in MailerSend.

Listen for events on your MailerSend account so your integration can automatically trigger reactions. You can create a webhook directly from your account.

# Webhooks overview

# Setup

Currently, you can create a webhook using API endpoints listed below or directly from your account. Read more

# Available events

These are all the events you can listen to and send a notification for.

Event Description
activity.sent Fired when your email was sent from our sending servers. We are now waiting for a response from the receiving servers.
activity.delivered Fired when your email was successfully delivered with no errors.
activity.soft_bounced Fired when your email was not delivered because it soft bounced.
activity.hard_bounced Fired when your email was not delivered.
activity.opened Fired when the recipient received your email and opened it.
activity.clicked Fired when the recipient clicked a link in your email.
activity.unsubscribed Fired when the recipient unsubscribes from your emails.
activity.spam_complaint Fired when the recipient marks your emails as spam or junk.

# Payload example

Our responses contain fat payloads including the information about the event-related object so there is no need to make an additional API request.

An example of activity.sent event:

  "type": "activity.sent",
  "domain_id": "yv69oxl5kl785kw2",
  "created_at": "2020-11-27T10:08:08.298647Z",
  "webhook_id": "2351ndgwr4zqx8ko",
  "url": "https://your-domain.com/webhook",
  "data": {
    "object": "activity",
    "id": "5fc0d006b42c3e16e1774882",
    "type": "sent",
    "created_at": "2020-11-27T10:08:06.258000Z",
    "email": {
      "object": "email",
      "id": "5fc0d003e7a5e7035446aa32",
      "created_at": "2020-11-27T10:08:03.923000Z",
      "from": "test@mailersend.com",
      "subject": "Test email",
      "status": "sent",
      "tags": null,
      "message": {
        "object": "message",
        "id": "5fc0d003f718c90162341852",
        "created_at": "2020-11-27T10:08:03.017000Z"
      "recipient": {
        "object": "recipient",
        "id": "5f6887d6fd913a6523283fd2",
        "email": "test@mailersend.com",
        "created_at": "2020-09-21T11:00:38.184000Z"
    "morph": null

# Security

Webhook requests made by MailerSend include a Signature header. It contains a string generated by hashing the data sent to your webhook endpoint with an individual Signing Secret. A signing secret is a random string that is generated when you are creating a webhook.

Verifying a signature:

// $signature - a header sent by MailerSend, please refer to your framework
// or PHP manual on how to read the Signature header

// $requestContent - please refer to your framework or PHP manual on how to read the request content

$computedSignature = hash_hmac('sha256', $requestContent, $signingSecret);
return hash_equals($signature, $computedSignature);

# Retrying failed webhooks

When your webhook receives a response other than a 2xx code from your endpoint URL or if the endpoint doesn’t respond within 3 seconds, it will show up as a failed attempt in the log section of your webhook. If it receives a 2xx, then it will show as a success.

If a webhook call fails, MailerSend will retry the call a couple of times, waiting 10 seconds between the first and second attempt, and 100 seconds between the second and the third attempt. This is to avoid hammering the application you want to send the information to.

# Useful tools

Webhook.site or Pipedream.com are useful tools for testing webhooks quickly, seeing how it works, and inspecting what's being sent—without any coding on your side.

# FAQs

  • How do i track back the Message i've sent via SMTP relay back to a webhook?

If the message was sent successfully, our SMTP relay will send you back a 250 Message queued as XXXXXX response that can be parsed to an ID used in our Messages endpoints, and in webhooks that Message ID can be found at data.email.message.id.

If you want full interoperability, we encourage you to use our Email API, for the best results.

# List webhooks

If you want to have information about webhooks, use this GET request:

GET https://api.mailersend.com/v1/webhooks

# Request parameters

Parameter Type Required Limitations Details
domain_id string yes

# Get a webhook

Get a single webhook, use this GET request:

GET https://api.mailersend.com/v1/webhooks/{webhook_id}

# Create a webhook

Create a webhook using this POST request:

POST https://api.mailersend.com/v1/webhooks/

# Request parameters

Parameter Type Required Limitations Details
url url yes
name string yes Max: 191
events array yes
enabled boolean optional
domain_id string yes Existing hashed domain ID

# Update a webhook

Update a webhook using this PUT request:

PUT https://api.mailersend.com/v1/webhooks/{webhook_id}
Parameter Type Required Limitations Details
url url optional
name string optional Max: 191
events array optional
enabled boolean optional

# Delete a webhook

Delete a webhook using this DELETE request:

DELETE https://api.mailersend.com/v1/webhooks/{webhook_id}
Last updated: 11/29/2021, 1:49:54 PM