Webhook vs API: What’s the Difference?

webhook vs api


Webhook vs. API: 5 Key Differences and Similarities

  • APIs need instruction to retrieve or manipulate data.
  • Webhooks make automated calls based on a specific event or events.
  • Both are used to help systems or web services communicate and share or transfer data.
  • APIs are most useful for rapidly changing data.
  • Webhooks are most useful for less frequent changes in data.

When you want websites, web apps, and other systems to communicate, you might use an API or a webhook. But the two are not interchangeable, and they are useful for very different tasks. We look at the difference between webhooks and APIs and where you might have seen both tools in use in your daily life.


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Webhook vs. API: The Basics

In simple terms, APIs and webhooks are both ways that help different technologies communicate. They facilitate the syncing and relay of data between two apps or systems. They both do this in different ways. An API has to have an instruction to do things. A webhook does it on its own depending on set criteria or conditions.

An API communicates from a specific server to an endpoint, perhaps a URL. When given the right instructions to do so, the API can create and edit items, list items, or delete them.

Webhooks are automated messages or instructions from one point to another. These messages or calls occur when specific conditions arise, which are predetermined for that particular webhook. This could be someone registering their interest in a product on a website. The webhook knows to send an instruction automatically to email that potential customer about the product in question. The instruction doesn’t need to happen in real-time.

Webhook Definition

Webhooks can be referred to as reverse APIs, as they tend to be communications from a website to a server, rather than the other way around. But this term is misleading. When learning about webhooks, the key difference is that the request for data doesn’t need to be initiated at the server end. An API will continue to ask for data no matter how many times it has been updated if you keep giving it the instruction to do so. A webhook will only work to the criteria given, so data should only transfer when a new event that fits within those criteria occurs.


When to Use Webhooks

Webhooks may be more useful than APIs for systems that demand real-time updates. Some developers may also use a webhook when an API is not in place, for whatever reason. However, a webhook needs a set of instructions or logic to prompt it to send or receive data, so it gives a developer less control than an API.

Webhooks will only send or request data when a new event occurs. This means that if there is system downtime, updates or other crucial data could be missed. Webhooks aren’t simply automated calls; specific criteria must be fulfilled in order for them to make a call.

Think of webhooks like your brain telling you you’re tired because you haven’t slept for a while, or hungry because you missed lunch. That’s how webhooks work. They base the data they send or request on the scenario they’re experiencing.

Set up a webhook by registering a URL to notify another system or app when certain events occur. As long as the route for data transfer is available through HTTP POSTs, webhooks will continuously provide new data based on the logic you provide them. The POST request asks the server to accept and store or use the data provided.

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Webhooks You May Have Heard of

Real-life examples of webhook usage you’re probably aware of include:·

·   MailChimp – Every time someone signs up for your email newsletter, that’s a webhook at work.

·   Stripe – The Stripe app and dashboard notifies its users whenever payments are on the way via webhooks and even supports users setting up purpose-built webhooks.

·   eBay – A webhook has sent every email that tells you you’ve been outbid or you’ve sold an item. Plus, eBay can even link to Zapier, a popular automation tool that uses webhooks for a range of business needs.

API Definition

An application programming interface (API) is a common communication method between applications, platforms, browsers, servers, or other external systems that need to share data. When you make a request for data, the APIs at both ends of the data transfer complete that request. Data usually arrives in JSON format. Activating your API is called polling, and every time you poll you’re requesting more data. This can lead to wasted resources, as if there are no new data updates to receive, those API calls use resources for nothing. An API is a bit like a text message you send to get your friend to do something, whereas the webhook works off a metaphorical to-do list.

There are literally thousands of APIs out there – over 23,000 according to ProgrammableWeb. IronWorker uses RESTful or REST API, which stands for Representational State Transfer, and is a streamlined API allowing data transfer to best use the existing architecture of the web. Some apps will use multiple APIs to communicate with a variety of services.

When to Use APIs

APIs are most useful when data is constantly changing or expanding. As mentioned, it’s not resource-friendly to request data constantly if there are no changes. Webhooks suit this purpose better, as they will only request data when there’s an update. APIs are ideal for dealing with ever-changing data streams or updates, such as e-commerce or any system that needs to receive information from multiple sources on a regular basis. An API connection usually starts with an HTTP GET request. These types of HTTP requests demand specific data from a specified resource.

APIs in Real Life

Real-life use cases for APIs that you should find all too familiar include:

·   Uber – The Uber app uses APIs to communicate between users, drivers, and customer support and allows developers to create their own external application using Uber’s API.

·   Houndify – Houndify uses RESTful API combined with voice activation to help users create speech to text apps or even improve robotics projects.

·   Slack – a popular communication service for many organizations, Slack’s RESTful API helps collate data ranging from internal messages to files from Dropbox using multi-step processes called workflows.

Webhook vs. API: Which Is Better?

Although this is a common question, hopefully, you can see that neither webhooks nor APIs can be considered “better,” as they both perform different tasks. Most developers will use both webhooks and APIs to get the most out of the abilities and benefits of both. A worker system with high scalability allows you to create your own event-based data transfers via webhooks and keeps your crucial systems talking all the time with the relevant APIs. It’s never been about one or the other – only about how you can maximize the workability of both.


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