Transformer Calculator

Enter primary and secondary turns with primary voltage to calculate secondary voltage, turns ratio, current ratio, and power.

Primary Turns (Np)

Secondary Turns (Ns)

Primary Voltage Vp (V)

Primary Current Ip (A) — optional

Secondary Voltage (Vs)

Turns Ratio (Np:Ns)

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Type

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Secondary Current (Is)

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Apparent Power (VA)

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Transformer Formulas

Vs = Vp × (Ns / Np)

Turns Ratio a = Np / Ns

Is = Ip × (Np / Ns) = Ip × a

Power: Vp × Ip = Vs × Is (ideal)