Thawing Time Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/9/2026
In the refrigerator, count on about 10 hours of thawing per kilogram of food; in cold water changed regularly, count on about 1 hour per kilogram. A 1.5 kg chicken therefore takes about 15 hours in the refrigerator, or 1.5 hours in cold water.
Explanation
Thawing is a sensitive step for food safety: between 4°C and 60°C, bacteria multiply rapidly, which is why thawing at room temperature isn't recommended for meat, poultry, and fish — the outside of the food can reach a temperature favorable to bacterial growth well before the center has thawed. Both methods in this calculator stay within a safe temperature range: in the refrigerator (4°C or below), thawing is slow but the food stays out of the risk zone the whole time — this is the recommended default method, especially for large cuts. In cold water (never lukewarm or hot), placed in a watertight container and changed roughly every 30 minutes, thawing is noticeably faster, about ten times quicker than in the refrigerator, while still staying at a temperature that limits bacterial growth. These times are order-of-magnitude estimates: the food's shape greatly influences the actual result — a flat, thin fish thaws noticeably faster than a compact cut of the same weight, like a roast — and refrigerator thawing time also depends on its exact temperature, which varies from one appliance to another. Once thawed, food must be cooked promptly and never refrozen raw, which would multiply temperature cycles through the risk zone; to then estimate the cooking time for thawed meat, see our meat cooking temperature calculator.
Example: a 1.5 kg whole chicken
Inputs
Food weight: 1.5 kg.
Calculation
In the refrigerator: 1.5 × 10 = 15 hours. In cold water: 1.5 × 1 = 1.5 hours.
Result
This chicken needs about 15 hours to thaw in the refrigerator (plan the day before), or about 1.5 hours in cold water changed regularly if time is short.
Frequently asked questions
Can food be thawed at room temperature, on the counter?
This isn't recommended for meat, poultry, and fish: the food's surface reaches a temperature favorable to bacterial growth well before the center has thawed, increasing the risk of contamination. Safe methods remain the refrigerator, cold water changed regularly, or the microwave (immediately followed by full cooking).
Why does cold water thaw ten times faster than the refrigerator?
Water conducts heat (or cold) much more efficiently than air: it's in direct, constant contact with the food's entire surface, whereas the air in a refrigerator transfers heat more slowly. Changing the water regularly (roughly every 30 minutes) maintains this temperature gap and speeds up the process further.
Should food be cooked immediately after thawing in cold water?
Yes: unlike refrigerator thawing, where the food stays continuously at a safe temperature, cold-water thawing gradually pushes the food out of that safe range as it warms up — it must therefore be cooked without delay once thawed, and never put back in the refrigerator for later use. This is a good time to adjust the amounts to cook with our recipe portions calculator, rather than thawing more than needed.