Simulator
See hot spots before you buy.
Pick a construction, set the burner size, and watch heat move from the flame to the rim. The evenness readout shows how close the edge gets to the center.
Heat Lab · live model
Watch heat spread across a pan
Edge-to-center evenness
Heating…
Reaching steady state
Simplified 1-D diffusion model using approximate thermal diffusivity for each construction (clad values are thickness-weighted estimates). It illustrates why conductive cores spread heat sideways; it is not a lab measurement of any specific pan.
What the simulator shows
Bare stainless keeps heat trapped over the flame, so the center scorches while the edges stay cool. Tri-ply and copper core spread heat sideways quickly. Cast iron spreads heat slowly but stores lots of it once fully preheated, which is why it needs a long preheat.
Tips from the model
- Match burner size to pan size. A small burner under a big pan exaggerates hot spots in every material.
- Preheat longer with low-conductivity pans like cast iron and carbon steel.
- Use a conductive core for sauces and delicate cooking where scorching ruins the dish.
Next: learn how to cook on stainless without sticking or compare metals in the Material Lab.
About this tool
How the simulation works
The Heat Lab models a slice across a pan as 60 points and applies a simplified one-dimensional heat-diffusion equation. Heat is added where the burner is (you set its width), spreads sideways according to the construction's thermal diffusivity, and is slowly lost to the surroundings. The color bar shows temperature, and the evenness readout is the coolest point divided by the hottest.
Methodology and limitations
- Diffusivity values for clad constructions are thickness-weighted estimates, not measurements of any specific pan.
- The model is 1-D, so it ignores the pan's thickness, the walls and food in the pan.
- It illustrates relative behavior, showing why conductive cores spread heat sideways, rather than predicting actual temperatures.
- Evenness shows "Heating…" for the first few seconds, until the pan has warmed enough for the ratio to be meaningful.
| Experiment | What you'll see |
|---|---|
| Bare stainless vs tri-ply, small burner | Stainless stays hot in the middle; tri-ply spreads to the edges |
| Tri-ply vs copper core | Copper core reaches the edges faster |
| Cast iron, wide burner | Slow but steady heating, why cast iron needs a long preheat |
| Any pan, burner much smaller than pan | A hot center; why matching pan to burner matters, especially on induction |
Turning it into cooking decisions
If your burners are small or uneven, a conductive core (tri-ply, 5-ply or copper core) makes the biggest difference. If you cook on gas and adjust heat constantly, copper core's fast response shows. Read the Copper Core analysis and D3 vs D5.
Frequently asked questions
Is the Heat Lab a real measurement?+
No. It's a simplified model to illustrate how heat spreads, not a lab test of any product.
Why does bare stainless show a hot spot?+
Stainless conducts heat poorly, so heat stays above the burner.
Why does copper core spread heat fastest?+
Copper has the highest thermal conductivity among common cookware metals.
What does evenness mean?+
The coolest point's temperature divided by the hottest, as a percentage.
Why does cast iron heat so slowly?+
Its low diffusivity means heat spreads slowly, but its mass stores heat once hot.
Does burner size matter?+
Yes. A burner much smaller than the pan creates a hot center, especially in poorly conducting pans.
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<a href="https://theskilletlab.com/heat-lab">Heat Lab: See How Heat Spreads in a Pan</a> via <a href="https://theskilletlab.com/">The Skillet Lab</a>Free to link and quote with attribution. Last updated October 16, 2026.