🔋 Ohm's Law Calculator
Enter any two values to solve for the remaining two. V = IR  |  P = IV = V²/R = I²R

Enter Two Known Values

Leave the values you want to calculate blank (or zero).

V = I × R   |   P = V × I   |   P = I² × R   |   P = V² / R
⚠ Please enter exactly two values.

Results

Quick Reference

FindKnownFormula
Voltage (V)I, RV = I × R
Voltage (V)P, IV = P / I
Voltage (V)P, RV = √(P × R)
Current (I)V, RI = V / R
Current (I)P, VI = P / V
Current (I)P, RI = √(P / R)
Resistance (R)V, IR = V / I
Resistance (R)V, PR = V² / P
Resistance (R)P, IR = P / I²
Power (P)V, IP = V × I
Power (P)V, RP = V² / R
Power (P)I, RP = I² × R