Change Cart button to Backorder on product page

Shopify Discussion

Topic summary

Goal: Change the product page “Add to Cart” button to “Backorder” based on stock and selling settings.

Requested behavior:

  • If inventory policy allows continuing to sell when out of stock and the selected variant’s stock ≤ 0, show “Backorder”.
  • If the customer’s selected quantity exceeds the current available stock, show “Backorder”. Otherwise, keep “Add to Cart”.

Current attempt:

  • JavaScript added in product.liquid. The basic checks (variant exists and variant.available == true) work, but the logic that reads current stock/quantity comparison is failing.
  • The actual code snippet was not provided in the post, so specifics of the bug are unclear.

Context/terms:

  • Variant: a specific option combination of a product (e.g., size/color).
  • Inventory policy “continue”: continue selling when out of stock.

Links provided for debugging:

  • Store: www.volleyballshop.com.au
  • Example product URL with variant parameter.

Status: No solution or code fix provided yet; the poster requested help to implement and improve the quantity-vs-stock comparison. Discussion remains open.

Summarized with AI on February 23. AI used: gpt-5.
1

Hello,

I am trying to set ADD TO CART button that will change to BACKORDER when product inventory management is continue and product variant stock is <=0 or when ordered quantity is bigger than current quantity in stock.

I have tried to use javascript which I added to the bottom of product.liquid:

If I use only first 2 conditions (variant && variant.available == true) it shows for all variants of course but it works.

I am assuming that the issue is probably in the next 2 conditions when I want to work with current stock quantity.

The shop url is www.volleyballshop.com.au

Please, would anyone be able to help me make this working and even improve it that it would be able to compare the selected quantity with the current available quantity?

Thank you in advance for all comments and tips.

2

Link to the product detail page: https://www.volleyballshop.com.au/collections/volleyball-shoes/products/wave-lightning-z6-french-blue-white-ired?variant=40519779188942