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Test Mailchimp Webhooks with HookTest

Test Mailchimp webhooks for subscriber, campaign, and list events. Use HookTest to create a free webhook URL, point Mailchimp at it, and inspect every request in real time — headers, body, and signature included.

Quick Start

Get Mailchimp webhooks flowing to HookTest in under a minute:

  1. Create a HookTest URL. Go to hooktest.dev and click Create Bin. Copy the webhook URL.
  2. Add it to Mailchimp webhook settings. Paste the HookTest URL as your webhook endpoint in the Mailchimp developer dashboard. Select the events you want to receive.
  3. Trigger an event and inspect. Perform an action in Mailchimp (or use their test/sandbox mode) and watch the request appear in HookTest in real time. Check headers, body, and query parameters.

Common Mailchimp Webhook Events

These are the most commonly tested Mailchimp webhook events. Each one triggers an HTTP POST to your webhook URL with a JSON payload.

EventDescription
subscribeNew subscriber added to list
unsubscribeSubscriber opts out
campaignCampaign is sent
cleanedEmail address cleaned from list

Verifying Mailchimp Signatures

Mailchimp signs every webhook request using the X-Mailchimp-Signature header. You should always verify this signature in production to confirm the request actually came from Mailchimp and was not tampered with in transit.

When testing with HookTest, you can inspect the raw signature header value in the request details. This is useful for verifying that your signature verification code handles the header format correctly before deploying to production.

See the official Mailchimp webhook docs for the full signature verification algorithm and code samples.

Why Test Mailchimp Webhooks?

Webhook handlers are notoriously hard to debug. You cannot see what Mailchimp is sending until your endpoint receives it, and errors in your handler can cause silent failures — missed payments, lost data, or broken integrations.

HookTest gives you full visibility into every request before you write a line of handler code. Create a bin, point Mailchimp at it, and see exactly what arrives: HTTP method, headers (including signatures), body, and query parameters. Once your handler is ready, use webhook forwarding to send requests to your local server in real time.

Start testing Mailchimp webhooks

Create a free webhook URL in one click. No signup required.

Create Free Webhook URL

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