Novel tools and techniques are provided for implementing stored-value instrument purchase functionality for online shopping systems. In various embodiments, a computing system might assess content and/or information presented in a checkout page of a retailer website, the checkout page listing items selected by a user for purchase and a total purchase amount. The computing system might autonomously modify the checkout page by generating a user-selectable option therewithin, the user-selectable option comprising an option to purchase the items using a gift card available for purchase from a service provider. In response to selection of the user-selectable option, the computing system might provide a purchase interface that presents the user with a process to purchase a gift card having a gift card value. After completing purchase of the gift card, the computing system might apply the gift card value toward the total purchase amount within the checkout page.