Kiln Curve Simulator

Schedule
Adjust the sliders to rebuild the schedule · press Play to simulate the firing
Current20 °C
PhaseIdle
Elapsed0.0 h

Target

Cone 6

Schedule

45 min
70 °C/h
140 °C/h
20 min
110 °C/h

Presets

Playback

Schedule output

Total time— h
Peak temp— °C
Heat work— °Ch
Suggested cone—
Energy estimate— kWh

Segments

SegProgramTime

Firing is a schedule, not a temperature

A kiln does not care about your peak temperature in isolation. Clay and glaze respond to heat work — the combined effect of how hot it got and how long it stayed there. Two firings that both reach 1222 °C will produce different pots if one soaked for an hour and the other did not. That is why potters measure firings in cones, not degrees.

The four segments of a firing

  • Candle — a hold at around 100 °C. This drives off mechanical water slowly. Skip it on thick or damp work and you risk a steam explosion.
  • Early ramp — up to 600 °C. This is where chemically bound water leaves the clay and organic matter burns out. Keep it slow; most kiln failures happen here.
  • Main ramp — 600 °C to peak. The glaze begins to melt and the body densifies.
  • Soak — a hold at peak. This evens out the load and lets a glaze heal over pinholes.

Reading the chart

The curve is drawn from the segment maths, not from a lookup table. Change any slider and the whole schedule is recomputed: the total time, the heat work figure and the energy estimate all follow. The colour of the curve tracks temperature — clay orange low down, kiln gold at the peak, glaze blue as it cools — and the kiln graphic beside the chart changes with it.

Two schedules the calculator will warn you about

An early ramp faster than 110 °C/h below 600 °C, and a main ramp above 200 °C/h. The first risks blowing up your load; the second gives uneven glaze melt and shortens element life.

Always cool with the lid closed

Crash cooling puts the glaze in tension against the body, which is a reliable way to produce crazing. The cooling segment here assumes natural cooling with the lid shut.

Try these experiments

  1. Load the Bisque 06 preset and note the total time. Now raise the early ramp to 250 °C/h and watch the warning appear while the total time drops.
  2. Load Glaze 6, then increase the soak from 20 to 90 minutes. The peak temperature does not change but heat work climbs — that is the whole point.
  3. Compare the Raku and Stoneware 10 presets. Raku is fast and short; stoneware is slow and long. The energy estimate reflects that difference.

Related tool references

  • Electric Kiln — Controlled, repeatable heat — the studio's most consequential machine.
  • Pyrometric Cone — A small clay pyramid that measures heat work, not just heat.
  • Kiln Shelf — The floor of every layer in the kiln.
  • Kiln Vent — Remove the fumes before they reach the room.