Best practices, Developers & APIs

What Is a Webhook?

Aleksandra Duło, 25 September 2023


In today’s age, email marketing has become an essential part of any successful digital marketing campaign. As businesses strive to increase their engagement and conversion rates, they rely on various tools and technologies to make it happen. One of the most popular technologies used in email marketing is webhooks. But what exactly is a webhook, and how does it work in the context of email marketing?


source: Google Trends

In this article, we’ll explore everything you need to know about webhooks and how they can help you optimize your email marketing strategy.

Read on to discover how you can use this powerful tool to take your email marketing to the next level.

Maximize your email deliverability and security with EmailLabs!

What Exactly Is A Webhook?

These days, businesses rely heavily on automation to streamline their workflows and improve efficiency. Webhooks have become an essential part of this automation process, allowing local and web apps to share data with each other in real-time without the need for constant manual intervention.

A webhook is a simple and powerful tool that enables real-time data transfer between different applications or web services. When an event occurs in one application, the webhook sends a notification to another application, triggering a predefined action. This process vastly simplifies tasks that would otherwise require human intervention, saving time and reducing the likelihood of errors.


How Do Webhooks Work?

Webhooks rely on a simple client-server architecture to function. The client app initiates the process by sending a request to a server with a specific URL. The server application then waits for an event to occur and sends a notification to the client app via the URL specified in the initial request.

To set up a webhook, the client application needs to provide a URL where the server application can send notifications. Once the webhook is set up, the server application will send a notification to the specified URL whenever specified event triggers occur. The client application can then process this notification and perform the predefined action.

Webhooks can be used for a wide range of applications, from sending real-time notifications to updating customer records or triggering a specific action in response to a user’s behaviour.

Tracking Events is Easy Using Webhooks

  1. Initiation: The process begins with an application, referred to as the “sender” or “client app.” This client initiates the webhook by sending an HTTP request, most commonly a POST request, to a server-side application (webhook endpoint). This request contains information about the event or data the client wants to convey.
  2. Registration: The server-side application receives this request and registers the webhook. The webhook has a specific URL address to which the client sends requests. This is the endpoint to which the client directs its queries.
  3. Events: The server-side application waits for the occurrence of a specific event that is relevant to the client. This event could be something like a new email, a database change, user account activation, etc.
  4. Notification: When the event for which the webhook is registered occurs, the server-side application sends a notification to the client. This notification is typically an HTTP request, often a POST request, containing data related to the event. The client can now process this data and take appropriate actions.
  5. Data Processing: The client application receives the notification and processes the data according to the tasks it needs to perform. This might involve updating a database, sending an email, notifying a user, or other actions defined in the application’s logic.

Webhooks operate asynchronously, meaning the client doesn’t need to constantly check the server for new data or events. Instead, the server informs the client only when a specific event occurs. This helps optimize performance and reduce response times.

Webhook vs. API When to Use?

At first glance, a webhook might seem similar to an API (Application Programming Interface). However, there are some key differences between the two. Webhooks are often called ‘reverse APIs’.

API calls are much harder to implement than webhooks as they require the development of custom code. In contrast, all you need to set up a webhook is a single POST request (i.e., an HTTP request) and a URL to receive the data.

APIs are also typically slower than webhooks as they rely on polling to check for new data. This means that the API will only retrieve data when it makes a request to the server. Webhooks, on the other hand, receive notifications in real-time – as soon as the event occurs.


In summary, webhooks are better suited for real-time notification handling, whereas APIs are employed for application integration and data retrieval in a more controlled manner.

What Is a Webhook in the Context of Email Marketing?

At this point, you’re probably wondering how webhooks fit into the world of email marketing.

In the context of email marketing, a webhook is a tool that allows you to send real-time notifications to your email marketing platform whenever a specific event occurs. For example, you can set up a webhook to notify your email marketing platform whenever a new customer is added to your CRM system.

This process can be used to trigger a variety of different actions, from sending a welcome email to the new customer to adding them to a specific email list.

Webhooks can be used to send data from a wide range of sources, including CRM systems, eCommerce platforms, social media applications, and other web apps. This makes them an extremely versatile tool that can be used to optimize your email marketing strategy in an endless number of ways.

If you are using EmailLabs services to boost your email deliverability and engagement rates, enabling webhooks will empower you to track the statuses of the emails you send. This will allow you to easily check whether an email has been delivered and opened, all without worrying that this crucial data will be deleted when the TTL expires. It’s also very easy – you can do so directly from your EmailLabs account settings.


Choose EmailLabs now and discover how effective your webhook-based email marketing efforts can be!

How Webhooks Benefit Your Email Marketing Strategy?

Properly set up webhooks offer a number of distinct advantages to your email marketing efforts, some of which may not be obvious at first glance.

How to run EventAPI in EmailLabs?

Instant Notifications

One of the biggest benefits of using webhooks in email marketing is receiving instant notifications. With webhooks, you no longer need to manually check for requested data or updates. Webhooks allow you to receive real-time updates about email opens, clicks, bounces, and more. You can quickly respond to customer behaviour and adjust your email campaigns accordingly.

Instant notifications enable effortless tracking of various metrics that you might find important for your email marketing strategy. To illustrate the point, let’s say you want to track the number of soft bounces that occur in your email list or discover the percentage of your emails that get marked as spam.


source: Camapign Monitor

In the past, you would need to manually review your email logs to find this information. With webhooks, you can set up an automated process that will track this data for you and instantly inform you of any new developments. This way, you can quickly identify any issues with your email delivery or engagement rates and take action to fix them.

Better Automation

Webhooks can also improve automation in your email marketing campaigns. By integrating webhooks with your email marketing platform, you can automate tasks such as list management, subscriber segmentation, and personalized messaging.

For example, you can set up a webhook to automatically add new subscribers to your email list or to send a follow-up email to subscribers who have opened a particular message.


CNN, for example, sends its subscribers a welcome email from a particular section only after confirming their email address. Above, a message from CNN’s Royal News section.

Enhanced Personalization

Webhooks allow you to deliver a more personalized experience for your subscribers. By tracking subscriber behavior in real-time, you can tailor your email content and offers based on their interests and actions. If a subscriber has recently purchased a product, you can use webhooks to send them targeted offers or recommendations based on their purchase history.


Improved Deliverability

Relying on webhooks in email marketing can also improve your email deliverability rates. If you use webhooks, you’ll be able to track unsubscribed addresses and identify invalid emails more efficiently, which in turn will help you maintain a clean email list and prevent being flagged as spam.

By keeping up a high deliverability rate, you can ensure that your emails are reaching the intended audience and improving the overall success of your email marketing strategy.

Maximize your email deliverability and security with EmailLabs!

Are There Any Limitations of Webhooks?

While webhooks are an excellent tool for improving email marketing strategies, it’s essential to be aware of their limitations to ensure their effective use. Here are some of the potential challenges to consider when using webhooks in email marketing:

Security Concerns

One of the biggest concerns when using webhooks is security. As webhooks rely on a URL to send data, there is always the risk that someone could discover this URL and gain access to sensitive information. To mitigate this risk, it’s important to rely on a reputable email marketing platform and reliable Email API that takes security seriously.

EmailLabs has a long history of safeguarding customer data and takes numerous industry-leading measures to ensure the security of our webhooks. But we understand that data safety is a shared responsibility, which is why we also recommend taking some basic precautions on your end to further protect your data.

Always use HTTPS when setting up webhooks to ensure that your data is encrypted in transit. You should also consider using a firewall to restrict access to the webhook URL to authorized IP addresses only. Finally, don’t forget to keep the URL secret and change it regularly to further reduce the risk of data breaches.

Data Loss

Another potential issue when using webhooks is data loss. Since webhooks receive data only once a specified event happens, there is always the risk that data could be lost if the server connection is interrupted. Although webhooks usually attempt to send the data again if the connection is lost, they won’t do so infinitely – after a certain amount of tries, the system will stop.

In this instance, APIs could be a better option as they send you an error message if the connection is lost, allowing you to take action accordingly. However, this advantage comes at the cost of increased complexity, as APIs require custom code to function properly.

Limited Functionality

Webhooks are not a cure-all solution for email marketing. While they can be used to automate various tasks and improve your email campaigns, they are essentially one-directional tools. This means they can only send data from one application to another – they cannot receive data.

To overcome this limitation, you can use webhooks in combination with other tools, such as APIs. By combining the strengths of different tools, you can facilitate more complex processes that would otherwise be impossible to achieve with webhooks alone.


On top of it, not all apps allow for webhook integrations, which might limit your options. Fortunately, with a little bit of research, you can find reliable third-party apps that offer webhook integration, even for those programs that don’t support them natively.


Webhooks are powerful tools that can be used to improve your email marketing strategy in a number of ways. By automating tasks, enhancing personalization, and improving deliverability, webhooks can help you optimize your email campaigns and boost your bottom line.

All in all, webhooks are an essential part of modern email marketing. If you’re not already using them to share data, we highly recommend that you consider doing so. They shine even more when coupled with other practices like APIs, so don’t be afraid to experiment and find the best solution for your needs.

If you are looking for a reliable email delivery service that supports webhooks, look no further than EmailLabs. Our platform makes it easy to set up and use webhooks and take advantage of their many benefits. With our services, you can boost your email delivery to the inbox – it takes us 0.16s on average!

Don’t wait any longer – contact us today and discover how our platform can help revolutionize your email game!

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