If you have a store with multiple products following the same pricing logic but with different default/base prices then you don't have to create a unique calculator for each product. You can use the same calculator with a variable - "shopify_product_price" instead of the constant value (price) in the formula. The variable - "shopify_product_price" would automatically detect the default price set by you for each product.
You are a Rug / Carpet seller with different qualities of rugs in your store. You may want to use the Custom Price Calculator app to calculate the price of the rugs based on the area selected by the customers.
Here, the pricing logic may be the same, however, the material price of each rug might vary. Let's assume you set the price as $2 per m. sq. for the standard rug and $5 per m. sq. for the premium in the respective product settings. For the two different products, you can use the same calculator by using the variable - "shopify_product_price" in the formula.
It will automatically detect $5 when applied to the premium rug