Ohms Law Calculator

Solve V, I, or R from the other two (V = I × R).

Ohms Law Calculator helps you solve V, I, or R from the other two (V = I × R). Enter voltage (v), current (a), and resistance (ω), review the breakdown, and use the guidance below to understand what the number means — and what it does not. What the Ohms Law calculator does Ohms Law Calculator is built for everyday questions — shopping, home, travel, hobbies, and tech. Solve V, I, or R from the other two (V = I × R). You enter voltage (v), current (a), and resistance (ω), then Simple Calculators computes the result instantly. Defaults are chosen to be easy to read — change any field to match your situation. How the math works Choose what to Solve for (Voltage, Current or Resistance) and fill in the other two: Voltage (V) in volts, Current (A) in amps, Resistance (Ω) in ohms. Ohm’s law says voltage = current × resistance, so current = voltage ÷ resistance and resistance = voltage ÷ current. Power is then worked out as voltage × current, in watts. The formula: V = I × R (so I = V ÷ R and R = V ÷ I). V is voltage in volts, I is current in amps, R is resistance in ohms.