Let's say you sell homemade pasta and set a unit quantity of 100 g at $7. This means that your customers will be able to buy it in multiples of 100 grams: 200, 300, 400 grams, etc. The cost will go up accordingly.
The products in the store will be displayed with the price for the unit you specified. If you add several units, weight or other values in the product card and in the shopping cart will be recalculated.
How to set up? The feature is available in the Product Catalog → Product card → Unit of measurement
More on selling products by weight and length 👉 https://help.tilda.cc/online-store/catalog/sell-by-weight-and-length