A shopper picks Large in red, and the cart gets Small in black. The store still loads and nothing shows in Shopify's admin, so it usually comes to light through a return or an annoyed email. Merchants in the Shopify Community trace it to three causes again and again.
Free tool: Free store break check: cart, checkout, search and links, as a shopper sees them
Enter your store address. A test shopper adds two variants straight to the cart and checks it got the right ones at the right prices; no order is placed. It doesn't click your theme's own button, so theme-script faults need a real browser: join the early-access list and ask for a free real-browser run of one product on desktop and mobile, done by us.
?variant= number in the address bar after selecting it.If the URL changes but the cart is wrong, the product form's hidden id field isn't updating, which is a theme or app script problem. If the URL doesn't change either, the variant picker itself is broken.
Pick a non-default variant on a product, on desktop and on your phone, add it, and read the cart. It takes a minute, and it's the check uptime monitors can't do: the page loads fine while the cart is wrong.
Free tool: Free store break check: cart, checkout, search and links, as a shopper sees them
Enter your store address. A test shopper adds two variants straight to the cart and checks it got the right ones at the right prices; no order is placed. It doesn't click your theme's own button, so theme-script faults need a real browser: join the early-access list and ask for a free real-browser run of one product on desktop and mobile, done by us.
When did a wrong variant (or wrong price) last end up in a customer's cart, and how did you find out?
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