๐ฌ Science
Ohm's Law Calculator
Ohm's law, V equals I times R, connects three quantities so that knowing any two determines the third. Power comes from combining it with P equals V times I, which is why a resistor's wattage rating matters as much as its resistance.
How it works
What do you know
Voltage
Current
Resistance
Voltage
Current
Resistance
Power
Power
Conductance
Frequently asked questions
How do I use the Ohm's Law Calculator?
Fill in the fields above โ the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.