# Calculate U, R, I and P online

Online calculator for calculating voltage, current, resistance and power

## Calculate Ohm's law and power online

This fuction calculate the voltage U , the current I , the resistance R or the power P . Two of the values must be known.

Enter two of the four values, then click the 'Calculate' button.

Online calculator U, R, I and P

 Input Voltage U µV mV V kV Current I µA mA A kA Resistance R mΩ Ω kΩ MΩ Power P µW mW W kW MW GW Decimal places 0 1 2 3 4 6 8 10 Resultate Voltage U Current I Resistance R Leistung P

## Ohm's law and power

Ohm's law is a basis of electrical engineering and electronics. It indicates the relationship between voltage, current and electrical resistance. The law says that the voltage is equal to the current multiplied by the resistance.

 Voltage $$\displaystyle U=R · I$$ $$\displaystyle U=\sqrt{P · R}$$ $$\displaystyle U=\frac{P}{I}$$ Current $$\displaystyle I=\sqrt{\frac{P}{R}}$$ $$\displaystyle I=\frac{U}{R}$$ $$\displaystyle I=\frac{P}{U}$$ Resistance $$\displaystyle R=\frac{P}{I^2}$$ $$\displaystyle R=\frac{U^2}{P}$$ $$\displaystyle R=\frac{U}{I}$$ Power $$\displaystyle P=U · I$$ $$\displaystyle P=I^2·R$$ $$\displaystyle P=\frac{U^2}{R}$$