This should probably work with EXTRA code, perhaps KolAsim (moderator) has a solution for this.

With the existing possibilities of WebSite X5 alone it probably won't work.

Eventually the customer could calculate the surface himself and put the amount for example 1,572 x 80 EUR. I check it is possible - the amount does not have to be an integer.

Correction - the quantity is set to an integer but in the basket it is possible to change it to not integer. But how to do the quantity in the shop as not integer?

Incomedia would actually have to add this function to the shop so that customers would have 2 input fields for length and width for corresponding products.

The shop operator would then only have to specify the units of measurement (e.g. meters, inches, etc.) and a price per unit of area (e.g. square meters, square inches, etc.).

But it is questionable whether this wish will at some point be implemented by Incomedia for the WebSite X5 shop.

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Unfortunately, I am not a Javascript expert and cannot create such a script.

Any tricks with the options in the shop are difficult to implement and not particularly customer-friendly.

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A possible implementation would be an ordering option using a contact form with the corresponding input fields to request all the required information.

Otherwise wait for KolAsim (Modrator) or other users of WebSite X5, maybe the problem has already been solved somehow.