# Testing and Tools
source: https://developer.mastercard.com/mastercard-gateway/documentation/testing/index.md

## Recommended paths {#recommended-paths}

Select the path that matches your role and integration requirements.

|                                 If you are a...                                  |                                                                                                                Then focus on...                                                                                                                 |                                                                                                             Recommended reading                                                                                                              |
|----------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| **Enterprise merchant**, a large merchant integrating directly with Gateway APIs | Using test environments and test card numbers to validate payment flows before going live, test scenarios such as success, decline, timeout, AVS/CVV, and 3DS, and verify integration with order management, fulfilment, and reporting systems. | * [Test Cards](https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-cards/index.md) * [Transaction Errors](https://developer.mastercard.com/mastercard-gateway/documentation/testing/trans-error/index.md)         |
| **Payment service provider**, a PSP, aggregator, or payment facilitator          | Provisioning test merchant profiles and supports merchants during integration testing and certification. Uses test cards to validate platform-level flows and test marketplace, tokenisation, 3DS, and retry logic across merchants.            | * [Testing your Integration](https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-your-int/index.md) * [Test Cards](https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-cards/index.md) |
| **Software vendor**, an ISV embedding payment flows into platforms               | Building payment integrations, plugins, and platforms on top of gateways. Uses test cards for automated testing, CI/CD pipelines, and demo and certification flows.                                                                             | * [Test Cards](https://developer.mastercard.com/mastercard-gateway/documentation/testing/test-cards/index.md)                                                                                                                                |

## API reference {#api-reference}

Testing uses the same API endpoints as production integrations.

For a complete list of supported APIs, see [API Reference](https://developer.mastercard.com/mastercard-gateway/documentation/api-reference/index.md).