Voltage Calculator
Calculate voltage using Ohm's law (V = I × R) or the power formula (V = P / I). Enter current and resistance to find voltage.
Enter current and resistance to calculate voltage.
Voltage Formula (Ohm's Law)
V = I × R
Voltage (V) is the electrical potential difference that drives current through a circuit. It equals the product of current (I) in amps and resistance (R) in ohms.
Alternative Voltage Formulas
V = P / I (from power)
V = √(P × R) (from power and resistance)
V = √(P × R) (from power and resistance)
Example: A circuit has 3 A of current and 10 Ω resistance.
V = 3 × 10 = 30 V
V = 3 × 10 = 30 V
FAQ
What is voltage?
Voltage is the electrical pressure that pushes current through a conductor. It's the energy per unit charge, measured in volts (V).
What is a safe voltage for humans?
Generally, voltages below 50 V DC or 25 V AC are considered less dangerous, but safety depends on many factors including current path and body resistance.
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Last updated: 2026-08-08