Enter the horsepower, voltage, efficiency, and power factor into the calculator to convert hp to amps. This calculator can also evaluate the hp volts, efficiency, or power factor given the other variables.

HP to Amps Calculator

Using Voltage
Poles & Frequency

Enter exactly 1 value to calculate the other

Calculator Operations Required Inputs
Convert Horsepower to Amps Total Horsepower
Convert Amps to Horsepower Total Amps

HP to Amps Formula

The following formula is used to calculate the total horsepower from amps.

A = HP * 746 / (V* n * PF) 
  • Where A is the amps
  • HP is the horsepower
  • V is the volts
  • n is the efficiency
  • PF is the power factor

To calculate amps from HP, multiply the hp by 746, then divide the result by the product of the volts, efficiency, and power factor.

Horsepower (HP) to Amps (A) Conversion Table — Common Voltages (Assumes η = 0.90, PF = 0.85)
Horsepower (HP) 1‑phase 120 V (A) 1‑phase 240 V (A) 3‑phase 208 V (A) 3‑phase 230 V (A) 3‑phase 460 V (A)
¼2.031.020.680.610.31
â…“2.711.350.900.820.41
½4.062.031.351.220.61
¾6.093.052.031.830.92
18.124.062.702.451.22
1½12.186.094.063.671.83
216.248.125.414.892.45
324.3612.188.117.343.67
540.6020.3013.5212.236.12
7½60.9130.4520.2918.359.17
1081.2140.6027.0524.4612.23
15121.8160.9140.5736.6918.35
20162.4281.2154.1048.9224.46
25203.02101.5167.6261.1630.58
30243.63121.8181.1573.3936.69
40324.84162.42108.2097.8548.92
50406.05203.02135.25122.3161.16
60487.25243.63162.30146.7773.39
75609.07304.53202.87183.4791.73
100812.09406.05270.50244.62122.31
* Rounded to 2 decimals. Assumes motor efficiency η = 0.90 and power factor PF = 0.85. 1 HP = 746 W. Single‑phase: I = HP × 746 / (η × PF × V). Three‑phase: I = HP × 746 / (η × PF × √3 × V).

HP to Amps Definition

HP to amps is the conversion from the standard unit of mechanical power to electrical power of amps.

HP to Amps Example

How to calculate HP to Amps?

  1. First, determine the total horsepower.

    Measure the horsepower of the engine.

  2. Next, determine the volts.

    Measure the volts.

  3. Next, determine the efficiency.

    Calculate the efficiency.

  4. Next, determine the power factor.

    Calculate the power factor.

  5. Finally, calculate hp to amps.

    Calculate hp to amps using the formula above.

FAQ

What is horsepower?

A horsepower is a standard unit for electrical power that is equal to exactly 746 watts.

How is Amps calculated from HP?

If you are converting directly from watts, you simply need to divide the watts by 746 to get horsepower. If you are converting from Amps, you must include more information about the motor as described in the formula A = HP * 746 / (V* n * PF).

hp to amps formula