Calculatee All calculators Read the lesson POWER · INTERACTIVE CALCULATOR Ideal Transformer Voltage Ratio Calculator Calculate a transformer's ideal voltage or winding turns from its primary and secondary ratio. Choose the unknown and enter the other values to see the rearranged equation and result.
How it works Vp/Vs = Np/Ns
Ideal AC transformer only: ignores winding loss, core loss, leakage and saturation. The voltage values must use the same convention (for example both RMS). This is not a mains wiring guide.
Worked example For 12 V AC RMS at the primary, 120 primary turns, and 60 secondary turns: Vs = 12 × 60/120 = 6 V AC RMS, ideally.
Before you use the result For a step-down transformer, the secondary has fewer turns. Select any one unknown, and enter the other three known values.
Understand the lesson → Check component tolerances and device limits before building a real circuit. Report an error .