About

Following a recipe exactly is the key to perfect cooking, but microwave instructions are often written for a specific wattage - usually 1000W or 1100W - which rarely matches the appliance sitting in your kitchen. Using the wrong time can result in food that is either dangerously undercooked or disappointingly rubbery.

This converter solves that problem by rescaling the cooking duration based on energy density. It preserves the total energy (Joules) required to cook the food, ensuring your leftovers, popcorn, or mug cakes come out exactly as the recipe intended, regardless of your machine's power.

Formulas

The calculation maintains the total energy applied to the food. Energy (Joules) is Power (Watts) multiplied by Time (Seconds). Therefore, the relationship is:

P_old × T_old = P_new × T_new

Rearranging to solve for the new cooking time:

T_new = T_old × P_oldP_new

Reference Data

If Recipe Says (1000W)	700W (Compact)	900W (Mid-Size)	1200W (High-End)
1 min 00 sec	1m 26s	1m 07s	0m 50s
2 min 00 sec	2m 51s	2m 13s	1m 40s
3 min 30 sec	5m 00s	3m 53s	2m 55s
5 min 00 sec	7m 09s	5m 33s	4m 10s
10 min 00 sec	14m 17s	11m 07s	8m 20s

Frequently Asked Questions

Yes, the physics of energy transfer remains the same. However, lower wattage microwaves might heat unevenly during long defrost cycles, so it is often better to use a slightly lower power setting (e.g., 50%) for a longer time rather than full power for a shorter calculated time.

Check the sticker inside the door frame or on the back of the unit. Standard "High" settings are typically: Compact (700W), Standard (1000W), and Large/Inverter (1200W).

Not linearly. As you can see from the formula, it is a ratio. For a 20% power increase, you need roughly 17% less time. Guessing often leads to overcooked edges.