Kiln Load Calculator

How many pieces fit on the kiln shelves, how many firings a batch needs, and the firing cost per piece.

Shelf length cm

Shelf width cm

Shelves you can load in one firing

Count the shelf positions the kiln actually has, including any you can stack on props.

Shape of the pieces

Your own packing fraction %

Leave at zero to use the figure for the shape above. Measure a real load once and use that figure.

Footprint of one piece cm

The widest dimension of the footprint, which is usually the rim of a bowl or the width of a mug handle.

Height of one piece cm

Used to check the load against the usable height of the kiln.

Gap between pieces cm

Two centimetres is a working figure for small ware, more for a wide foot or a runny glaze.

Pieces in the batch

Cost of a bisque firing

Electricity or gas, plus a share of element wear for the firing.

Cost of a glaze firing

Minutes to load and unload one firing min

Used for the labour figure. Loading carefully takes longer than loading fast and breaking things.

Your time per hour

Optional. Used for the labour cost of loading and unloading.

Reset

Free calculator by Handcraft worked examples and methodology No account, nothing stored.