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Showing inventory on product page on Shopify
Product inventory is the amount of a particular products which is available for sale in your shop at the moment. The inventory count can be added on Shopify to any page, but the most popular way to place it is either on a product or a collection page.
To display inventory on Shopify you need to edit your liquid theme code.
How to show quantity in stock on Shopify
To show in stock or out of stock level there is no other way than editing your liquid code.
Shopify out of stock message
To change the out of stock message you need to go to your theme’s language settings.