SMPS efficiency calculation

Hello !

I build a SMPS driven by arduino (see post and I would like to calculate the efficiency of my project. Is there a way to easily get this, or, I have to use amp-meter and voltage meter on the output and input of the SMPS ?

I found this related page ! But in that case i need 4 of these devices !

Can anyone help ?

Just measure the power in and the power out and calculate the ratio seems the easiest way. Otherwise there are losses in several components so it would be pretty hard to calculate them individually and total them. The inductor has resistive losses, the cap leaks, the diode conducts in reverse for at least some amount of time, everything else at least heats up some so.....