Webhook Simulator

What is a Webhook Simulator?

A webhook simulator is a tool that lets you control exactly how your webhook endpoint responds to incoming requests. Instead of just capturing webhooks, a simulator lets you configure the HTTP status code, response body, headers, and timing of the response.

This is important for testing edge cases that are difficult to reproduce in production. How does your payment provider handle a 500 Internal Server Error from your endpoint? How many times will GitHub retry a failed webhook? What happens when your endpoint takes 30 seconds to respond? A webhook simulator answers all these questions.

Requex.me includes a built-in webhook simulator. Click "Edit Response Settings" in your dashboard to configure custom responses for your test endpoint, all completely free.

Simulation Scenarios

Set status 500 to trigger Stripe's exponential backoff and verify your idempotency logic handles duplicate deliveries. Set status 503 to confirm your provider marks the endpoint unavailable. Set status 200 with a 6,000ms delay to hit Shopify's 5-second timeout and watch it queue a retry.

Custom response bodies handle verification challenges without any server code. For Slack URL verification, configure the response body and Requex returns it to Slack automatically. For Facebook or any webhook that requires a challenge-response handshake, same approach.

Custom response headers let you test integrations that inspect specific response headers. All configuration happens in Response Settings in the dashboard. Change the simulated response mid-session without reconfiguring your provider URL.

Provider Retry Behavior

Understanding how each provider retries failed webhooks is critical. Use the webhook simulator to map out each provider's behavior:

How to Set Up a Webhook Simulation in 3 Steps

1. 1

   Get your webhook URL

   Open Requex.me. A unique webhook URL is generated instantly. Copy it and configure it as your endpoint in Stripe, GitHub, Shopify, or any other provider.

2. 2

   Configure your simulated response

   Click Response Settings in the dashboard. Set the HTTP status code your endpoint should return (e.g. 500 to test retries), add a response body, set custom headers, or add a delay in milliseconds to simulate a slow server.

3. 3

   Trigger events and observe provider behavior

   Send a test event from your provider's dashboard. Watch it arrive in Requex.me in real-time, see the response your simulation returned, and check whether the provider retried and when.

Real Testing Scenarios

Related Resources