Volts to Amps Calculator
This volts to amps calculator turns power and voltage into current in amps. Enter the watts and the volts and the volts to amps calculator returns the current. Going from volts and watts to amps takes both values, since current is power divided by voltage, and this tool works for DC and single phase supplies.
Results
The Volts to Amps Calculator is part of our AC & Three Phase collection. Browse more ac & three phase to size, convert, and check your work alongside this tool.
What volts and watts to amps conversion means
Current is how much charge flows each second, and going from volts and watts to amps splits the power across the voltage. This volts to amps calculator divides the watts by the volts, so a bigger load at the same voltage draws more amps. Finding amps with watts and volts is how you check whether a circuit or a cable can carry a load, which is what the volts to amps calculator returns.
The volt to ampere formula
The volt to ampere formula divides power by voltage:
W is the power in watts and V is the voltage in volts, so current is simply wattage divided by voltage. This form holds for DC and single phase AC at unity power factor; on three phase you divide by the square root of three times the line voltage times the power factor. The volts to amps calculator uses the single phase form, which is why finding amps with watts and volts is a one step job here.
Convert volts and watts to amps example
A 2300 W load on 230 V. To convert volts and watts to amps:
So the load draws 10 amps. Change the watts and the volts to amps calculator updates the current at once, working as a quick volts to amps converter.
How to use the volts to amps calculator
Enter the power in watts and the voltage in volts, and the volts to amps calculator returns the current in amps. Read the watts off the nameplate and the volts from the supply. To convert volts and watts to amps you need both, since voltage alone does not set the current; this convert voltage to amps calculator handles the division.
Reading the volts to amps calculator result
The current is what a breaker and a cable must carry, so it drives the wire size and the breaker rating, both chosen above the running current for safety. A load on a low voltage pulls more amps than the same load on a high voltage, which is why high current circuits use heavier cable. Compare the amps here with the cable rating before you connect a load. The volts to amps calculator gives the running current; add a margin for the breaker.
When to find amperage with watts and volts
- Sizing a cable when you find amperage with watts and volts
- Checking a breaker with the volts to amps calculator
- Reading a nameplate where you calculate amps with volts and watts
- Confirming a plug or lead can carry the load
Common volts to amps calculator mistakes
- Using voltage alone. You cannot convert volts and watts to amps without the power, so enter both.
- Ignoring power factor. On motors the real current runs above wattage divided by voltage.
- Sizing cable to the running amps only. Add a margin, since breakers and cables are rated above the load.
Tips for accurate current
- Read the watts and volts from the same nameplate and supply.
- Size cable and breakers above the running current.
- Apply the power factor for motors and reactive loads.
Calculate amps with volts and watts
To calculate amps with volts and watts, treat the watts as the job and the volts as the pressure doing it: more job at the same pressure needs more flow, which is more current. This is why the same appliance draws about twice the current on 120 V that it draws on 240 V, and why countries on higher mains voltage use thinner cable for the same load. Calculate amperage from watts and voltage before you pick a cable, since the current, not the power, sets the conductor size. The Ohm’s law calculator links current, voltage, and resistance when you know a different pair of values.
Finding amps with watts and volts for DC and AC
Finding amps with watts and volts follows the supply. For DC and single phase AC at unity power factor, current is wattage divided by voltage, the form this tool uses. A power factor below one raises the current for the same real watts, since some current is reactive, so a motor draws more amps than its real power suggests. On three phase, divide by the square root of three times the line voltage times the power factor. Matching the form to the supply keeps the current honest, which matters because an underestimate here undersizes the cable and the breaker.
Volts and watts to amps chart
Single phase results from going volts and watts to amps, A = W divided by V:
| Power | Voltage | Current |
|---|---|---|
| 1000 W | 230 V | 4.35 A |
| 2300 W | 230 V | 10 A |
| 3680 W | 230 V | 16 A |
| 2000 W | 120 V | 16.67 A |
Volts to Amps Calculator FAQ
What is the volt to ampere formula?
The volt to ampere formula is A = W divided by V, current equals wattage divided by voltage. The volts to amps calculator applies it for you.
How do you convert volts and watts to amps?
Divide the power by the voltage. To convert volts and watts to amps for a 2300 W load on 230 V you get 10 A, single phase.
Can you find amps from volts alone?
No. Voltage alone does not set the current; you need the power too. That is why calculate amps with volts and watts uses both values.
Does this cover three phase?
This form is DC and single phase. On three phase, divide the power by the square root of three times the line voltage times the power factor.