Ohm's Law Calculator
Calculate voltage, current, resistance, and power using Ohm's Law and electrical formulas
Electrical Parameters
Enter known values to calculate unknown parameters
Ohm's Law: V = I × R. Power: P = V × I. Enter any two values to find the others.
For energy calculations
Ohm's Law Formulas
Basic Ohm's Law:
V = I × R
I = V / R
R = V / I
Power Formulas:
P = V × I
P = I² × R
P = V² / R
Energy Formula:
E = P × t (Energy = Power × Time)
Electrical Safety
Voltage Safety:
- 12V and below: Generally safe (low voltage)
- 24-48V: Low voltage, minimal shock risk
- 120V: Standard household, dangerous
- 240V+: High voltage, lethal
Current Effects:
- 1mA: Barely perceptible
- 5mA: Maximum safe current
- 10-20mA: Muscular control lost
- 50mA+: Possible cardiac arrest