kalkmate
Open app
Science
Science

Ohm's law calculator

Voltage, current, resistance — pick the unknown, fill in the rest. Power dissipation included.

Result · V = I × R
12V

Power dissipation: 24 W (P = V × I)

The relationship

V = I × R — voltage equals current times resistance. From that single equation you can rearrange for any of the three. Power follows from P = V × I, which also rearranges to P = I² × R or P = V² ÷ R.

Units

  • Volts (V) — electrical potential difference
  • Amperes (A) — current, charge per second
  • Ohms (Ω) — resistance to current flow
  • Watts (W) — power, energy per second
● Related

More calculators

Browse all →