Sous Vide Time Calculator (Cooking Time by Thickness)
How long a steak, fillet, sausage or meatball needs in a water bath before its centre reaches the temperature you want, from its thickness and starting temperature.
Results
The dashed line marks the value you entered.
What this tool does
Heat creeps into food by conduction, so the time grows with the square of the thickness: a steak twice as thick takes four times as long, which is why 'one hour per inch' rules mislead. The formulas are the one-term solution of the heat equation used in Baldwin's review of sous vide cooking, with a thermal diffusivity of about 1.3 to 1.5 × 10⁻⁷ m²/s for meat and fish. They give the time to bring the centre to the target; they say nothing about food safety, so for pasteurisation hold times use official tables.
Formula
slab: t = d² ÷ (π² α) × ln[4 ÷ (π θ)] · cylinder: t = d² ÷ (4 × 5.783 α) × ln(1.602 ÷ θ) · sphere: t = d² ÷ (4π² α) × ln(2 ÷ θ) · θ = (T_bath − T_core) ÷ (T_bath − T_start)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
sh | Shape of the food | — |
th | Thickness (diameter for cylinder or sphere) | mm |
t0 | Starting temperature of the food | °C |
tw | Water bath temperature | °C |
tc | Core temperature you want | °C |
al | Thermal diffusivity of the food | ×10⁻⁷ m²/s |
M | Time for the centre to reach the target | min |
H | The same time in hours | h |
Worked example
- Shape of the food1
- Thickness (diameter for cylinder or sphere)30 mm
- Starting temperature of the food5 °C
- Water bath temperature58 °C
- Core temperature you want57 °C
- Thermal diffusivity of the food1.4 ×10⁻⁷ m²/s
- Time for the centre to reach the target46 min
- The same time in hours0.76 h
Limitations
- This tool is informational only. It does not diagnose, treat or replace a qualified health professional. Speak to a doctor before making decisions about your health.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.