How do I test Core Checkout in the sandbox?

What is the sandbox for?

The sandbox environment allows you to test your Core Checkout integration without processing real payments. It is technically identical to production, but uses test data.

Your sandbox credentials

Your sandbox credentials are sent to you by email at onboarding. They include:

URL: sandbox-dashboard.corebycarlo.com
Email: your developer email address
Password: provided by email
OTP: 000000
**Lemonway ID : **provided by email

Once logged in, your test secret key is available under** Developer → Configuration.**

Your developer space

You can access your developer settings by clicking "Developer" in the menu. Two sections are available:

Configuration — This is where you set up your API integration. From here you can:

Open the API Documentation to follow the integration guide
Retrieve your API key, needed to authenticate your requests
Configure your Webhooks, the URL where Core sends the result of each payment to your server

Notifications — This shows the log of webhook calls sent from Core to your endpoint. For each call you can see the date, the event, the related transaction, the method, the target URL, the response status, the HTTP code, and the duration. Use this to check that your webhooks are being received correctly and to troubleshoot any failed delivery.

Test cards

👉 View test card numbers

Expiry date: any future date
CVV: any 3 digits

⚠️ Important — The sandbox dashboard gives access to the Checkout test environment only. It is separate from the production dashboard.

❓ Having trouble with access? Contact us at support@corebycarlo.com

Updated on: 10/06/2026