The free online resistor wattage calculator is used to calculate the wattage of the resistor, also explains; the formula for electric power, how to utilize the resistor wattage calculator, and also determines which resistor is in a circuit dissipates the most power. All you have to do is provide the respective inputs in the online resistor wattage calculator and click on the calculate button to avail outputs.

How do you determine the Wattage of a Resistor?

The wattage of a resistor cannot be found by its color code, but its size can find out. The size of a resistor varies depending on its wattage. For instance, The wattage (or power rating) of a resistor determines its size. The smallest carbon composition resistor has a power rating of 1/8 W, while the largest has a power rating of 5 W. The power rating of a 20 x 10 mm thick film chip resistor is 1/20 W, but the power rating of a 250 × 120 mm thick film chip resistor is 1 W.

Electric Power Formula

Electricity is defined as the flow of electrons. The potential difference W is the energy required per unit charge to transport a test charge from point A to point B while maintaining its kinetic energy. When electrons flow through a resistor, the total work done is: 

W = Q x V

I = Q/Δt

W = (I. Δt). V

P = W/ Δt = V. I

  • Where, W = total work done
  • Q = total charge of the electrons that passed through the resistor over a given period of time
  • V = potential difference 
  • I = current
  • Δt = time period

How to use the Resistor Wattage Calculator?

For circuits including several resistors, use the resistor wattage calculator as follows:

  • Choose a circuit type from the Circuit type drop-down menu.
  • From the drop-down list for My power supply has constant, select a known character from the current and voltage of the power supply. In the next row, enter the value of the known parameter.
  • Begin by entering the resistance of the resistors starting with Resistor 1 (R1). A new row appears each time you enter a resistance value to add the next resistance. You can use up to ten resistors in total.

Get to know similar concepts along with their calculators on the trusted portal Physicscalculatorpro.com and resolve all your doubts.

How do I determine which resistor in a circuit dissipates the most power?

In a series circuit, power is dissipated by the component with the highest resistance. The same amount of current runs through all resistors in a series circuit, and power is equal to the square of the current and resistance, I2R.

Since the voltage across the resistors remains constant and power is the product of voltage and current (VI), the component with the least resistance wastes the most power in a parallel circuit.

FAQs on Resistor Wattage Calculator

1. Is it necessary to use resistors with 12 volt LEDs?

LEDs can be powered by a variety of voltages, but the current in the circuit must be limited by a series resistor. An LED that receives too much current will burn out. LEDs, like other diodes, allow current to flow only in one direction: from anode to cathode.


2. Is it possible to get power from a resistor?

No. Converting different sources of energy into electrical energy is part of the power supply process. Resistors are used to transform electrical energy into heat. As a result, a resistor absorbs and dissipates power rather than supplying it to a circuit.


3. What is the definition of a quarter watt resistor?

The quarter-watt resistor has half the surface area of the half-watt portion, it can only radiate half as much heat. To avoid damage to the resistor, you should build the circuit so that the power dissipation of the resistor is roughly one-half of its rated power.


4. What is the definition of a power resistor?

When huge amounts of energy must be safely converted to heat using electrical energy as a medium, power resistors are used. They're employed as power dissipation devices that can be controlled, protection devices, and devices that replicate real-world demands.


5. Is it possible to utilize a resistor with a higher wattage?

The maximum amount of power that a resistor can dissipate is referred to as wattage. So substituting a greater wattage for a lower wattage has no effect.