# Testing
source: https://developer.mastercard.com/account-catalog-services/documentation/testing/index.md

Use this page to plan and execute Sandbox validation for the Account Catalog Services API. It covers the recommended workflow, positive and negative coverage, and the reference guides you need for endpoint-level execution.
Tip: Start all validation in Sandbox before moving to Production.

### Choose a testing method {#choose-a-testing-method}

Choose a testing method that best matches how you want to validate requests:

* [Insomnia Collection](https://developer.mastercard.com/platform/documentation/developer-tools/insomnia-collection/) - an alternative API client with a ready-to-use workspace. Download Insomnia collection [acs-insomnia-collection.zip](https://static.developer.mastercard.com/content/account-catalog-services/uploads/acs-insomnia-collection.zip) (18KB).
* [Reference Application](https://developer.mastercard.com/account-catalog-services/documentation/developer-tools/reference-app/index.md) - a working implementation you can run and inspect.
* Custom API client generated as per guidance in [API Basics](https://developer.mastercard.com/account-catalog-services/documentation/api-basics/index.md).

### Recommended testing workflow {#recommended-testing-workflow}

Use this sequence to validate the main endpoint families with a realistic flow:

Click the following links to learn about various examples of the Account Catalog Services API:

| Account Catalog Services API |                                                                                                                                                                                                                                                                                  Testing Details                                                                                                                                                                                                                                                                                   |
|------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Account Catalog Services API | * [Positive test scenario](https://developer.mastercard.com/account-catalog-services/documentation/testing/positive-testing/pan-registration-bau/mastercard-one-cred-testing/1-pan-reg-with-mc-one-cred/index.md) * [Negative test scenario](https://developer.mastercard.com/account-catalog-services/documentation/testing/negative-testing/pan-registration-bau/index.md) * [Test Scenarios](https://developer.mastercard.com/account-catalog-services/documentation/testing/positive-testing/pan-registration-bau-depricated/pan-registration-modification/scenario1/index.md) |
| Account Range Enablement API | * [Positive test scenario](https://developer.mastercard.com/account-catalog-services/documentation/testing/positive-testing/are-enablement/1-produg-comm-flexible-nter/index.md) * [Negative test scenario](https://developer.mastercard.com/account-catalog-services/documentation/testing/negative-testing/are-enablement/index.md)                                                                                                                                                                                                                                              |

Note: Currently PUT and DELETE operations are supported only for [MasterCard One Credential Testing](https://developer.mastercard.com/account-catalog-services/documentation/testing/positive-testing/pan-registration-bau/mastercard-one-cred-testing/1-pan-reg-with-mc-one-cred/index.md) and [ALM Commercial Flexible Interchange PAN](https://developer.mastercard.com/account-catalog-services/documentation/testing/positive-testing/pan-registration-bau/alm-b2b-pan/1-alm-b2b-pan/index.md). Note: Account Catalogue Services testing requires API onboarding. For more details, refer to the [Quick Start Guide](https://developer.mastercard.com/account-catalog-services/documentation/quick-start-guide/index.md).

## Next Steps {#next-steps}

* Consult the [API Reference](https://developer.mastercard.com/account-catalog-services/documentation/api-reference/index.md) for complete endpoint specifications, request and response schemas, and environment URLs.
* Refer [Codes and Formats](https://developer.mastercard.com/account-catalog-services/documentation/code-and-formats/index.md) for the complete list of response codes, reason codes, and formatting rules.
* If you run into issues, visit [Support](https://developer.mastercard.com/account-catalog-services/documentation/support/index.md) for FAQs and troubleshooting guidance.