addToCart

Add to cart is a common ecommerce action that allows a shopper to place a selected product, and optionally a chosen variant and quantity, into a persistent shopping cart for later checkout. The term may refer to a button, link, or other control labeled Add to cart on product detail pages.

When a user activates Add to cart, the system creates or updates a cart object associated with the user’s session. The action may be performed on the client side by updating a local cart state and then syncing with the server, or it may be handled entirely server-side. If the item is out of stock, the action is typically disabled or results in an error message. The item data often flows through inventory and pricing services to ensure accuracy at the moment of addition.

Common data captured with the action includes product ID, variant ID, requested quantity, price, and stock status. The cart is often presented via a mini-cart drawer or a cart page, showing updated totals and item summaries. The behavior may vary by platform, but the goal is to provide a reliable bridge between product selection and checkout.

Design considerations include the visibility and labeling of the button, accessibility via keyboard and screen readers, and immediate feedback on successful addition (such as a notification or cart preview). Performance and reliability are important to minimize delays. Some sites offer a Buy Now option as a separate pathway or maintain saved carts for guests and signed-in users.

Analytics typically track add-to-cart events for conversion and funnel analysis, with localization and tax/shipping rules influencing pricing and availability at checkout.