Size limits

The Input validations section, on the editor's Rules & limits tab, sets the sizes shoppers can enter, for your largest printable size, your stock width, or a sensible minimum.

Fields

There's one box each for width and height, or one for length on a product priced by length:

Required

Shoppers must enter it. On by default.

Minimum and Maximum

In the product's unit. The default is 1 to 9999.

Error message

Optional. Replaces both the too-small and the too-large message.

Hint after its name and Help line under the field

Optional words shoppers see with the field, such as "floor to lintel" and "Standard sizes: 2100 to 2200 mm" (see size hints).

What shoppers see

The size fields show the allowed range as a placeholder, such as "12–96". Outside it, they see "Width must be at least 12." or "Width must be no more than 96.", and Add to cart waits for a valid size.

The "From" price

The product page's "From $X" uses the minimum width and height (or length), in the cheapest material, with the default add-ons. Set realistic minimums so it means something.