Defrosting Time Calculator
How long frozen food takes to thaw in the fridge or in cold water, with the number of water changes needed.
Results
What this tool does
Thawing is the step people underestimate: a frozen turkey put in the fridge on Christmas Eve will still be frozen solid on Christmas morning. The guidance is simple arithmetic — roughly a full day in the fridge for every 2.3 kg, or half an hour per 450 g in cold water that is changed every thirty minutes so it never warms up. Neither method should ever be swapped for the kitchen counter.
Formula
fridge: 24 h per 2.27 kg ; cold water: 30 min per 0.454 kg
Variables
| Symbol | Meaning | Unit |
|---|---|---|
kg | Weight of food | kg |
FH | Thawing in the fridge | h |
FD | Thawing in the fridge | dias |
WM | Cold water thawing | min |
WH | Cold water thawing | h |
WC | Water changes needed | — |
Worked example
- Weight of food2 kg
- Thawing in the fridge21.1 h
- Thawing in the fridge0.88 dias
- Cold water thawing132 min
- Cold water thawing2.20 h
- Water changes needed3
Limitations
- The default values are typical reference figures, not measurements of your situation. Replace them with your own data whenever you have it.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
Frequently asked questions
Why not just leave it on the counter?
Because the outside thaws long before the centre does, and it then sits for hours in the range where bacteria multiply fastest while the middle is still frozen. Food safety agencies give three safe methods: in the fridge, in cold water changed every thirty minutes, or in the microwave followed immediately by cooking. The fridge is slowest and by far the most forgiving.