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Max Quantity For WC Shops is a simple extension for WooCommerce that only does one thing: it lets you set a max limit for the number of items that can be added to the cart, for each product, per order.
It’s like one of those signs at the grocery store that says, “LIMIT 2 PER CUSTOMER!” This plugin will not add a sign like that, but the quantity input field (pictured above) will hit a limit.
You can simply set a universal limit to affect all products in your WooCommerce store. If you prefer, you can set a different limit for each product, individually. Each product’s own limit will always override the universal limit.
This works for all products in your WooCommerce store: Simple and Variable products.
Customers do not have to be logged in for this to work. This works for guest buyers, as well as logged-in buyers.
Disclaimer
I am not affiliated with WooCommerce, WooThemes, or Automattic. I provide this plugin as a free service to the WP community (originally created for my own personal use).