Free workshop tool
Ohm’s Law & Power Calculator
Enter any two known electrical values and calculate voltage, current, resistance and power for quick bench checks.
DC / resistive calculation. This calculator uses basic Ohm’s law and power relationships. Reactive AC loads such as loudspeakers, transformers and inductive circuits are frequency-dependent and need additional analysis.
Formula reference
Core equations
Ohm’s law
V = I × R, I = V ÷ R and R = V ÷ I.
Power
P = V × I. Equivalent forms include P = I²R and P = V² ÷ R.
Related free tools & guide
Read: Ohm’s Law for Electronics Repair
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