# Checkout ## GetCustomCarrierRates - Get Mirakl custom carrier information - [POST /api/storefront/custom-carrier](https://developer.mirakl.com/content/connector/operator/shopify/app-operator-shopify/rest/public/openapi3/checkout/getcustomcarrierrates.md): Using to display the Mirakl shipment method during the checkout processCall FrequencyRecommended usage: - Each time we need to compute the Mirakl shipping fees during the checkout