Kiln builder
Design a kiln brick by brick. Four shapes, 3D model, honest brick counts with cutting optimization, and SVG export.
Tools
Pottery calculators
Free in-browser calculators for working potters. Each one takes the inputs you actually have and gives you a number you can use.
Energy calculator
How much energy does your kiln need? Insulation, heat loss, R-values, and fuel equivalents for electric, gas, or wood.
Element calculator
Size the heating wire for a studio-built electric kiln. Wire diameter, coil geometry, surface load, and a feasibility check against Kanthal's limits.
Slip casting calculator
Plaster and water for the mould, a casting slip mixed or corrected to the right gravity, and how long each cast stays in the mould as the session goes on.
About these calculators
Four calculators, three about the kiln and one about the mould and the slip that goes into it. All of them are free and run in the browser, with nothing to install and no account to make. They exist because the arithmetic behind a kiln or a casting is not difficult, only tedious enough that most people guess instead, and a guess about brick counts, element wire or a plaster batch costs real money.
Which one answers which question
Start with the kiln builder when you are deciding what to build. It lays a chamber up brick by brick in four shapes, counts what you actually need including the cuts, and exports dimensioned plans you can carry to the workshop.
Go to the kiln firing cost calculator when the kiln exists, on paper or in the yard, and the question is what it costs to run. It solves the wall layer by layer with conductivity that changes as the wall heats, adds the thermal mass of the brick and of the load, and returns kilowatt hours, cost per firing, and the power needed to get there. Gas and wood as well as electric.
Reach for the element calculator once you know the power and need the wire. It sizes Kanthal or Nichrome to a voltage and a target wattage, works out the coil geometry, checks the surface load against the alloy limit, and tells you how much wire to buy.
The slip casting calculator is for the work before the kiln. It weighs out the plaster and water for a mould at the consistency you choose, mixes or corrects a casting slip to a target specific gravity with its deflocculant, and times each cast in the mould, including how the casts slow down as the plaster takes on water over a session.
They hand work to each other
The three kiln tools are one chain and they know it. Size a chamber in the builder and send its dimensions to the energy calculator. Take the element power the energy calculator recommends and send that to the element calculator, which turns it into a wire diameter and a coil. Each handover carries the numbers across, so nobody is retyping a chamber size into three forms and mistyping it on the second.
The slip casting calculator is a chain of its own, laid out left to right on one page. The model you size the mould around is the cavity the slip has to fill, and the moulds you fill are the ones the casting column times.
What they will not do
None of them replaces a test firing. The energy model is steady state with a transient estimate on top, and it knows nothing about your door seal, your flue, or the way a particular kiln sulks in winter. The brick counts assume the wall gets laid the way the drawing shows it. The element figures are design figures, and the wire you buy carries its own tolerance. The casting session is a stated estimate built on the book's casts-per-session figures, and your own first cast is the number to trust over it.
What they are good for is sizing a project, comparing two wall builds honestly, and finding out before the brick is ordered that the electrical supply you have will not carry the kiln you drew.