# Test Cards
source: https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-cards/index.md

Use published test cards to simulate transaction responses. These cards trigger specific outcomes for transaction operations. When you access a card emulator, use the test merchant profile with the `TEST` prefix provided by your payment service provider.

### How to use test cards {#how-to-use-test-cards}

When the gateway creates a merchant ID, it also creates a duplicate merchant ID with the TEST prefix. If you use a card emulator, use the test merchant profile with the `TEST` prefix provided by your payment service provider.

To test your integration with simulated transactions, see the list of [Test Card Numbers](https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-cards/test-card-numbers/index.md).

### 3D Secure test cards {#3d-secure-test-cards}

"3‑D Secure Enrolled" means 3DS can be tested with these cards using the `PAYER_BROWSER` channel in the [INITIATE_AUTHENTICATION](https://mtf.gateway.mastercard.com/api/documentation/apiDocumentation/rest-json/version/100/operation/Authentication%3a%20%20Initiate%20Authentication.html?locale=en_US) API operation, but not with other channels.

Use test cards to validate payment and authentication scenarios in your integration. For 3‑D Secure authentication testing, see [Test your EMV 3-D Secure Integration](https://developer.mastercard.com/mastercard-gateway/documentation/security-and-fraud/authentication/3d-secure-auth/test-3ds-int/index.md).

### Gift cards {#gift-cards}

To test your integration with gift card numbers and response codes, contact your payment service provider for test data.