Ohm's law calculator for resistive DC circuits

Known pair Voltage (V) and current (A) Voltage (V) and resistance (Ω) Voltage (V) and power (W) Current (A) and resistance (Ω) Current (A) and power (W) Resistance (Ω) and power (W)

Voltage (V)

Current (A)

Calculate Copy summary

— Choose a pair and enter nonnegative values.

• 12 V and 2 A → 6 Ω and 24 W
• 12 V and 6 Ω → 2 A and 24 W
• 6 Ω and 24 W → 2 A and 12 V (positive magnitudes; no polarity)

Ideal resistive DC model. Does not calculate AC reactive loads, power factor, conductor sizing, protective devices, or NEC compliance.

V=I·R · P=V·I · P=I²R · P=V²/R. Example: 12 V and 2 A → 6 Ω and 24 W. Ideal resistive DC model only — not AC reactive loads, breaker sizing, or NEC compliance.