Volts to Amps Conversion Calculator
Convert volts to amps by entering the voltage and the electrical power in watts, or the resistance of the circuit.
Convert Volts and Watts to Amps
Convert Volts and Ohms to Amps
Current:
| Amps | |
| Milliamps |
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How to Convert Volts to Amps
Voltage is the electric potential difference in an electrical circuit, measured in volts. It might be easier to think of it as the amount of force or pressure pushing electrons through a conductor.
Electric current is a measure of the flow of electrons in a circuit, and is often measured in amperes.
Since these are different quantities or properties, to convert volts to amps, you need to use the Watt’s Law power formula or the Ohm’s Law formula.
The Watt’s Law power formula states that current = power ÷ voltage. Power is measured in watts and voltage is measured in volts. In AC circuits, use the RMS voltage as input and the output will be in RMS amps.
Volts to Amps Formula
Thus, to find amps substitute the volts and watts in the formula:[1]
I(A) = P(W) / V(V)
So, the current I in amps is equal to the power P in watts divided by the voltage V in volts.
For example, let’s calculate the amperage of a 100-watt light bulb at 120 volts.
amps = 100 W / 120 V
amps = 0.83 A
A 100-watt light bulb at 120 volts will draw 0.83 amps of current.
Convert Volts to Amps using Resistance
Ohm’s Law provides an alternate formula to find volts if amps and the electrical resistance are known. To calculate amps, divide the voltage by the resistance in ohms.[2]
I(A) = V(V) / R(Ω)
The Ohm’s Law formula states that the current I in amps is equal to the voltage V in volts divided by the resistance R in ohms.
For example, let’s find the current of a 12-volt circuit with 10 ohms of resistance.
amps = 12 V / 10 Ω
amps = 1.2 A
A 12-volt circuit with a resistance of 10 ohms will draw 1.2 amps of current.
Volts to Amps Chart
The table below shows volts converted to amps at various power ratings and RMS voltages.
| Voltage | Current | Power |
|---|---|---|
| 5 Volts | 1 Amp | 5 Watts |
| 5 Volts | 2 Amps | 10 Watts |
| 5 Volts | 3 Amps | 15 Watts |
| 5 Volts | 4 Amps | 20 Watts |
| 5 Volts | 5 Amps | 25 Watts |
| 5 Volts | 6 Amps | 30 Watts |
| 5 Volts | 7 Amps | 35 Watts |
| 5 Volts | 8 Amps | 40 Watts |
| 5 Volts | 9 Amps | 45 Watts |
| 5 Volts | 10 Amps | 50 Watts |
| 5 Volts | 11 Amps | 55 Watts |
| 5 Volts | 12 Amps | 60 Watts |
| 5 Volts | 13 Amps | 65 Watts |
| 5 Volts | 14 Amps | 70 Watts |
| 5 Volts | 15 Amps | 75 Watts |
| 5 Volts | 16 Amps | 80 Watts |
| 5 Volts | 17 Amps | 85 Watts |
| 5 Volts | 18 Amps | 90 Watts |
| 5 Volts | 19 Amps | 95 Watts |
| 5 Volts | 20 Amps | 100 Watts |
| 12 Volts | 0.4167 Amps | 5 Watts |
| 12 Volts | 0.8333 Amps | 10 Watts |
| 12 Volts | 1.25 Amps | 15 Watts |
| 12 Volts | 1.667 Amps | 20 Watts |
| 12 Volts | 2.083 Amps | 25 Watts |
| 12 Volts | 2.5 Amps | 30 Watts |
| 12 Volts | 2.917 Amps | 35 Watts |
| 12 Volts | 3.333 Amps | 40 Watts |
| 12 Volts | 3.75 Amps | 45 Watts |
| 12 Volts | 4.167 Amps | 50 Watts |
| 12 Volts | 4.583 Amps | 55 Watts |
| 12 Volts | 5 Amps | 60 Watts |
| 12 Volts | 5.417 Amps | 65 Watts |
| 12 Volts | 5.833 Amps | 70 Watts |
| 12 Volts | 6.25 Amps | 75 Watts |
| 12 Volts | 6.667 Amps | 80 Watts |
| 12 Volts | 7.083 Amps | 85 Watts |
| 12 Volts | 7.5 Amps | 90 Watts |
| 12 Volts | 7.917 Amps | 95 Watts |
| 12 Volts | 8.333 Amps | 100 Watts |
| 24 Volts | 0.2083 Amps | 5 Watts |
| 24 Volts | 0.4167 Amps | 10 Watts |
| 24 Volts | 0.625 Amps | 15 Watts |
| 24 Volts | 0.8333 Amps | 20 Watts |
| 24 Volts | 1.042 Amps | 25 Watts |
| 24 Volts | 1.25 Amps | 30 Watts |
| 24 Volts | 1.458 Amps | 35 Watts |
| 24 Volts | 1.667 Amps | 40 Watts |
| 24 Volts | 1.875 Amps | 45 Watts |
| 24 Volts | 2.083 Amps | 50 Watts |
| 24 Volts | 2.292 Amps | 55 Watts |
| 24 Volts | 2.5 Amps | 60 Watts |
| 24 Volts | 2.708 Amps | 65 Watts |
| 24 Volts | 2.917 Amps | 70 Watts |
| 24 Volts | 3.125 Amps | 75 Watts |
| 24 Volts | 3.333 Amps | 80 Watts |
| 24 Volts | 3.542 Amps | 85 Watts |
| 24 Volts | 3.75 Amps | 90 Watts |
| 24 Volts | 3.958 Amps | 95 Watts |
| 24 Volts | 4.167 Amps | 100 Watts |
| 120 Volts | 0.0417 Amps | 5 Watts |
| 120 Volts | 0.0833 Amps | 10 Watts |
| 120 Volts | 0.125 Amps | 15 Watts |
| 120 Volts | 0.1667 Amps | 20 Watts |
| 120 Volts | 0.2083 Amps | 25 Watts |
| 120 Volts | 0.25 Amps | 30 Watts |
| 120 Volts | 0.2917 Amps | 35 Watts |
| 120 Volts | 0.3333 Amps | 40 Watts |
| 120 Volts | 0.375 Amps | 45 Watts |
| 120 Volts | 0.4167 Amps | 50 Watts |
| 120 Volts | 0.4583 Amps | 55 Watts |
| 120 Volts | 0.5 Amps | 60 Watts |
| 120 Volts | 0.5417 Amps | 65 Watts |
| 120 Volts | 0.5833 Amps | 70 Watts |
| 120 Volts | 0.625 Amps | 75 Watts |
| 120 Volts | 0.6667 Amps | 80 Watts |
| 120 Volts | 0.7083 Amps | 85 Watts |
| 120 Volts | 0.75 Amps | 90 Watts |
| 120 Volts | 0.7917 Amps | 95 Watts |
| 120 Volts | 0.8333 Amps | 100 Watts |
You might also find out amps to volts converter useful.
References
- Miller, C., NFPA's Electrical References, National Fire Protection Association, 2004, Jones & Bartlett Learning, 67-75. https://www.google.com/books/edition/NFPA_s_Electrical_References/raUyIi7i-asC
- Miller, C., Ugly’s Electrical References, 2020 Edition, 2020, Jones & Bartlett Learning, 2. https://books.google.com/books?id=1kS8DwAAQBAJ