I like lattes, a lot. I bought a little Bialetti coffee maker to make near-espresso quality coffee and a small $2.99 milk frother to kick my Starbucks habit and make lattes at home. But the problem was, I could never get consistently good, frothy milk. It turns out milk has an optimum temperature for frothing, around 150-155 degrees Fahrenheit, or 65-68 degrees C. Get it too hot and the proteins necessary to form milk bubbles denature, making good foam unlikely. So the secret is knowing how long to heat it to get it to the perfect temperature for forming foam. This calculator uses the specific heat of (whole) milk (3.77 J/gK), the wattage of your microwave, and the amount of milk you're trying to warm up to calculate the amount of time you should microwave milk to make it foamable with a cheap little stirrer like mine. Happy foaming!