DIY · kitchen
DIYSteak

Steak Timer & Doneness Calculator

Every steak recipe says “three minutes a side”. Heat travels from both faces to the middle, and that takes time proportional to the square of the thickness — so the one number every recipe leaves out is the only one that decides the answer.

The steak

The pan

How do I know what my pan is at?

You cannot read it off the dial — the dial sets power, and the pan sets temperature. Two ways to find out:

Landmarks. Butter browns around 150 °C. Oil shimmers and thins at 180–200. A flicked drop of water breaks into beads that skate across the surface (the Leidenfrost point) from about 200. Most seed oils smoke around 230, and cast iron left dry will haze at 250–260. If it is smoking hard before the steak goes in, you are past searing and into burning.

Rough dial settings, for a heavy pan preheated 4–5 minutes. These are starting points, not measurements — hobs vary enormously:

Hob~200 °C~230 °C ~260 °C
Gasmediummedium-highhigh
Induction (1–9)678–9
Electric radiant (1–6)4–55–6 6, and slow to change

An infrared thermometer costs little and removes the guesswork entirely. Induction responds in seconds; radiant electric takes a minute or more to catch up, which is why it is the easiest hob to overshoot on.

Timing

Total in the pan
What to do
Everything else

Rest time is advice, not a simulation result. Resting is mostly about letting the fibres relax and reabsorb juice, which is not a temperature you can read off; the figure above is the usual guidance for this thickness. The simulated rest is stopped at the moment the middle reaches your target, because past that point it drifts towards the steak's mass-average, which is energetically right and not a thing anyone waits around to watch.

The rest is simulated, not assumed — scrub past the pull and you can watch the gradient collapse inwards, which is what resting actually does. The size of the carryover it produces still runs high, and the reason is known: the pan-to-meat contact conductance here (1100 W/m²K) is at the optimistic end, so the outer millimetres take on more energy than they should and push it inward once the pan is gone. Contact conductance and evaporation have to be calibrated against each other, and they have not been. The timings are not affected — those are set by how fast heat crosses the middle, and they match the independent model to the second. The carryover figure used above is the measured one.

Cook it

Runs the same simulation forward in real time. Sound needs one tap first.

0:00
Ready
Get the pan hot before you start the clock.

Through the middle

at the pull
turned
at the pull

Why the recipe time is wrong

Field notes

Thickness, not weight

Heat enters from both faces and has to reach the middle. That is conduction, and conduction time goes as the square of the distance — so thickness is the input that decides the answer. Weight tells you how many people it feeds and how far the pan sags when it lands; it moves the time by a few per cent. Every recipe that says “for a 250 g steak” is anchored to the wrong number.

Pull it before it is ready

When a steak leaves the pan the outside is far hotter than the middle, and that heat keeps moving inwards. A 25 mm steak drifts up about 4 °C while it rests; a 50 mm one about 6. If you take it out at the temperature you want to eat, you will eat it one doneness further on than you planned.

Flip more than you were told

The single dramatic flip is a photography technique. Turning every 30 seconds gets to the same core temperature sooner and with a narrower band of overcooked meat under the crust, because neither face spends long losing heat to the room. You trade some of the grill-mark contrast for a more even inside.

A cold pan is the real failure

A thin pan loses more surface temperature to a cold steak than it can replace, and the meat ends up steaming in its own moisture instead of searing. That is why cast iron is worth the weight, and why a non-stick pan — whose coating should not go past about 230 °C — is the wrong tool for a steak.

The probe beats all of this

Everything here is a model of a steak, not your steak. It does not know how flat yours is, how wet the surface is, or what your hob actually does. Use these numbers to know when to start checking, and let an instant-read thermometer make the decision.

Where the model stops

This is conduction only. It does not model the crust, water loss, fat rendering, or the evaporative cooling that pins a wet surface near 100 °C until it dries — which is why real times run a little longer than these, especially for the first minute. A bone is not modelled as a separate material, so treat T-bone times as the meat-only answer.

How this works

The page solves heat conduction across the steak in two dimensions — through the thickness and across the width — in small time steps — an explicit finite-difference solve of the one-dimensional heat equation. It is not a table of recipe times with your inputs looked up in it.

Each face is either against the pan or exposed to the room and they swap on your flip schedule, while both side edges lose heat to the room the whole time. Solving only through the thickness, as this page first did, makes every point at a given depth identical by construction — so “uneven” could not exist, and the edges that actually overcook were invisible. The pan side uses a contact conductance of roughly 1100 W/m²K for cast iron; the air side uses about 20, which covers free convection and radiation together. The steak’s own conductivity, density and specific heat come from the cut, because fat conducts heat more slowly than lean muscle.

The deliberate choice is not to use the usual one-term (Heisler) approximation. That is only valid once the Fourier number passes about 0.2, and a searing steak spends most of its time below that — precisely where the shortcut would be wrong. Solving it directly costs a few milliseconds and has no validity window.

A worked example

A 25 mm sirloin from the fridge, cast iron set to 230 °C, turned every minute, cooked to medium rare. The surface under the steak settles near 211 °C once the cold meat has pulled it down. The centre reaches the 51.9 °C pull temperature after about 5 minutes 40 seconds in the pan, and drifts up to 56 °C during a six-minute rest.

Cut the same steak 40 mm thick and it needs about 12 minutes 50 — not the 60% longer its thickness suggests, but well over twice as long.

Why does the timer want me to pull it below the temperature I asked for?

Because it is still cooking. The outside of a seared steak is far hotter than the middle, and that heat keeps travelling inwards after it leaves the pan. The page shows the carryover it expects for your thickness, and takes it off the target automatically.

Does weight really not matter?

Hardly at all for timing. At a fixed thickness, going from 180 g to 400 g changes the time by a few per cent — it is the same distance from the face to the middle, and the heat does not care how wide the steak is. Weight does affect how far the pan temperature sags when the steak lands, which is modelled, and it decides how many people you are feeding.

Why is flipping every 30 seconds faster?

A face that is not on the pan is losing heat to the room. Turning often keeps both faces near the pan temperature on average, so more heat goes in per minute and the gradient through the steak is gentler. The cost is that you do not build the same dark crust in one unbroken contact, which is what the single flip buys.

What if my pan is not on the list?

Pick the closest by thermal mass. A thick disc-base stainless pan behaves more like carbon steel than like a thin one; an enamelled cast-iron pan behaves like cast iron. The setting that matters most is the surface temperature, and the only reliable way to know yours is an infrared thermometer.

Can I use this for a reverse sear?

Not directly. A reverse sear brings the whole steak up slowly in a low oven and then sears it briefly, which is a different problem — the middle is already close to target before the pan is involved, and almost none of the time is conduction from a hot face. The times here are for a steak that starts cold and goes straight into a hot pan.

What this page assumes

Two-dimensional conduction through a rectangular cross-section — heat enters from the pan face, leaves the upward face, and leaves both side edges, which is what makes the rim and corners run ahead of the middle. Uniform meat, with a pan surface that sags on contact and then holds. Not modelled: the crust, moisture loss, fat rendering, evaporative cooling of a wet surface, bones, or a steak that is thicker at one end than the other. Times are a starting point for the first steak, and an instant-read thermometer is the only thing that knows when yours is done. Cooking times are guidance, not food-safety advice — if you are cooking for someone pregnant, elderly, very young or immunocompromised, follow your local food-safety guidance on internal temperatures instead.

Version history · 4 releases
  1. v3.142026-08-13The steak cross-section finally draws the right way up, the rest is simulated rather than assumed, and the readouts say what to do first
  2. v3.152026-08-13Evaporation modelled properly, the flip animation stops turning the pan upside down, and the tool now says what cadence to turn at and why
  3. v3.162026-08-13The steak page was wearing the egg timer's egg; the clock now sits with the bar it drives and the flip advice with the flip control
  4. v3.172026-08-13The resting steak sits on a plate, not the pan, the simulated rest stops at service, and the carryover question is settled

Releases in which this page changed, newest last. Derived from the archived copy of every release, not from notes written afterwards — so it reflects what actually shipped. Site-wide passes are left out; they are in the full changelog.

Egg Timer Calculatorboiled cook time from Charles D. H. Williams' (University of Exeter) closed-form solution to the heat-diffusion equation for a sphere: t = [M^⅔·c·ρ^⅓ / (K·π²·(4π/3)^⅔)] · ln[0.76·(T_egg−T_water)/(T_yolk−T_water)], with ρ=1.038 g/cm³, K=5.4×10⁻³ W/(cm·K), c=3.7 J/(g·K) — verified against all four of Williams' own published worked examples (57g egg from fridge/room temp, 47g and 67g eggs from fridge), matching to within rounding in every case. Poached reuses the identical equation with a 0.41× effective-mass adjustment, calibrated against published 2–5 minute poaching times, to account for a shell-less egg's flatter, faster-heating shape. Fried uses the semi-infinite-slab solution for one-sided conduction into a thin layer, with the same ρ/K/c thermal constants and a depth/pan-temperature/target-temperature triple per style calibrated to published pan-temperature ranges. Scrambled uses a lumped-capacitance exponential approach to pan temperature — valid because stirring keeps the mixture close to one temperature throughout — the same mathematical form as this site's Tea Brewing and Beverage Cooling calculators, calibrated against a published ~4-minute medium-doneness reference. Boiling point at altitude uses the same Clausius–Clapeyron model as the site's Altitude & Depth tool. All four are idealised models — real eggs are ellipsoidal with distinct white and yolk thermal properties, and frying and scrambling in particular involve geometry and technique this tool simplifies — so treat results as a strong starting point, not a guarantee down to the second. See Sources.