In today’s connected development landscape, building systems that talk to each other is the norm. From payment processors and CRM tools to notification systems and analytics platforms, how they communicate under the hood matters. A lot.

That leads to a common developer question: Should I use a webhook or an API for this?

Let’s break it down simply, without fluff, without sales talk. Just practical guidance on how each works, why they differ, and when to use which.

API vs Webhook: What’s the Core Difference?

• API (Application Programming Interface): You initiate the request. It’s a pull model, you ask the server for data or trigger actions.
• Webhook: The external service initiates the request. It’s a push model, you get notified when something happens.

How They Work

APIs are like placing an order at a restaurant. You (the client) tell the server what you want and wait for a response. You’re in control.

const getUser = async (id) => {
  const res = await fetch(`/api/users/${id}`);
  const user = await res.json();
  return user;
};

You can:

• Read or update data
• Control request timing
• Expect consistent responses

Webhooks, on the other hand, are like delivery notifications. You don’t ask; you just get told when your order is shipped.

app.post('/webhook/order', (req, res) => {
  const { orderId } = req.body;
  res.status(200).send("OK");

  // Process the order
});

You get:

• Real-time updates
• Fewer redundant requests
• Triggers for automation

When to Use APIs

Use APIs when you need control or orchestration:

• Fetch on Demand: A user loads a dashboard → fetch API data now.
• CRUD Operations: Create, read, update, or delete resources programmatically.
• Complex Workflows: When steps must happen in sequence, like processing a payment.
• User-Initiated Actions: “Click → request → update” style interactions.

Example: A dashboard shows real-time product info. Use GET /api/products/123 to load it when needed.

When to Use Webhooks

Webhooks shine in event-driven systems:

• Real-Time Notifications: Get notified the moment an event occurs (e.g. payment succeeded).
• Automated Triggers: “When X happens, do Y” flows (e.g. signup → send welcome email).
• Avoid Polling: Don’t waste resources checking every few minutes—get pinged when it matters.

Example: Stripe sends a webhook when a payment completes → your server updates the order → confirmation email sent.

Security Basics

API Security:

• Use OAuth, API keys, or JWT
• Enforce rate limits
• Sanitize input
• Always use HTTPS

Webhook Security:

• Verify webhook signatures
• Handle retries gracefully
• Use HTTPS for payload delivery

const crypto = require('crypto');

app.post('/webhook', (req, res) => {
  const signature = req.headers['x-signature'];
  const expected = crypto.createHmac('sha256', process.env.SECRET)
    .update(req.body)
    .digest('hex');

  if (signature !== expected) {
    return res.status(403).send('Unauthorized');
  }

  // Process webhook...
});

Local Testing: A Quick Tip

APIs: Easy to test with Postman, curl, or built-in tools.

Webhooks: Trickier—you need a public URL for external services to call. While tools like ngrok exist, you can also forward your local port with a single SSH command using a tool like Pinggy:

ssh -p 443 -R0:localhost:3000 a.pinggy.io

Now, external services can POST to your local /webhook endpoint—no deployments, no firewall changes.

Webhooks vs WebSockets?

They sound similar, but don’t confuse them.

Think of webhooks as push alerts, and WebSockets as live conversations.

Combine Them for Best Results

Most real-world systems don’t choose just one. Instead:

• Use webhooks for event notifications (e.g., order placed)
• Follow up with an API call for full data (e.g., GET order details)

This hybrid model keeps your architecture responsive and robust.

TL;DR Summary

Conclusion

Choosing between APIs and webhooks isn’t about one being better—it’s about using the right tool for the right job. APIs are deliberate and controlled. Webhooks are reactive and efficient.

References

1. Webhook vs API: Differences and When to Use What?
2. APIs
3. Pinggy's Official Website