Free Webhook Tester Online - TestMu AI (Formerly LambdaTest)

What is a Webhook Tester?

A webhook tester gives you a unique, throwaway URL that captures any HTTP request sent to it and shows the full details, method, headers, query string, source IP, and body, so you can see exactly what a service is sending. It is the fastest way to inspect and debug webhooks from providers like Stripe, GitHub, Shopify, or your own app without writing a receiver first. TestMu AI (formerly LambdaTest) runs the capture endpoint, and requests are kept for 24 hours.

Why use a webhook tester?

Webhooks fail silently when the payload is not what you expect, so seeing the raw request is the fastest way to debug an integration. A webhook tester helps you:

• See the exact payload: Inspect the real method, headers, and body a provider sends before you write any handler code.
• Debug without a server: Test a provider's webhook end to end without deploying a receiver or exposing localhost.
• Confirm delivery and retries: Watch requests arrive in real time and verify signatures, timestamps, and retry behavior.
• Share what you captured: Copy a request's details to hand off to a teammate or attach to a bug report.

How to Use the Webhook Tester

• Copy your webhook URL: Use the unique URL shown above; a new one is generated automatically per browser.
• Point a service at it: Paste it into a provider's webhook settings, or send a request with curl or your app.
• Watch requests arrive: Each incoming request appears in the list within a few seconds.
• Inspect the details: Select a request to view its method, headers, query params, and formatted body.
• Reset when needed: Use New URL for a fresh inbox, or Clear to remove captured requests.

What you can inspect in each request

Every captured request is broken down so nothing about the payload is hidden:

• Method and URL: The HTTP verb (GET, POST, PUT, and more) and the full path the sender used, including query parameters.
• Headers: Every request header, including content type, user agent, and provider signature headers you need to verify.
• Body: The raw payload, with JSON pretty-printed so you can read fields at a glance.
• Source and timing: The source IP and the time the request arrived, useful for confirming retries and delivery order.

Common use cases for a webhook tester

A throwaway capture URL is handy anywhere a service sends HTTP callbacks:

• Integrating providers: Inspect payloads from payment, git, and SaaS webhooks before writing a receiver.
• Verifying auth: Check signature and authorization headers, then reproduce them with the JWT decoder or Basic Auth generator.
• Inspecting JSON: Copy a captured body into the JSON Viewer to explore nested fields.
• Building test callbacks: Generate identifiers for your own webhooks with the API Key generator. TestMu AI builds these free developer utilities alongside its testing cloud of 10,000+ real devices and 3000+ browsers.

Frequently Asked Questions (FAQs)

What is a webhook?

A webhook is an automated HTTP request one service sends to a URL you control when an event happens, such as a payment or a push. Instead of you polling for changes, the provider pushes the data to your endpoint in real time.

What can I send to the webhook URL?

Any HTTP request. It accepts every method (GET, POST, PUT, PATCH, DELETE, and more) and any content type, including JSON, form data, multipart uploads, XML, and plain text, and records the full request for you to inspect.

How do I test a webhook without writing code?

Copy the unique URL this tool gives you, paste it into a provider's webhook settings or send a request with curl, and every incoming request appears here with its method, headers, and body. No server or receiver code is required.

Can I inspect the request headers and body?

Yes. Each captured request shows its method, full request headers, query string, source IP, and body. JSON bodies are formatted for readability, so you can confirm exactly what a provider is sending.

How long are captured requests kept?

Captured requests are stored for 24 hours and then removed automatically. The most recent 100 requests per URL are retained, so you can inspect a burst of webhooks without losing the latest ones.

Is the webhook URL private?

The URL contains a random, unguessable identifier, so only someone with the exact link can send to or view it. Treat it as a shared secret and generate a New URL if you have posted it somewhere public.

Does it respond to the sender?

Yes. The endpoint accepts the request and returns a 204 No Content response, which most webhook providers treat as a successful delivery, so you can confirm connectivity while you inspect the payload here.

Is the webhook tester free?

Yes, the TestMu AI webhook tester is completely free with no signup. You get a unique URL instantly and can capture and inspect as many incoming requests as you need directly in your browser.