**Power_out/efficiency = Power in**

That seems reasonable to me if you know the efficiency.

However, if you have no idea what the efficiency of a converter is that you just breadboarded i dont see how you can calculate the power in

The power output can be calculated simply with

**Power_out = Vout X Iout**

Since the input current of the converter is discontinuous how do you measure the power input of a converter?

I would of said that

**Power_In = I_Average X Voltage_in**

But how are you supposse to measure I_average?? When i say I_Average I mean AVERAGE not RMS.

What is the generally accepted practice here?