CFM to HP Calculator

Our easy to use cfm to hp calculator is designed to convert cubic feet per minute to horsepower (HP) for those dealing with air compressors, ventilation systems, and fluid dynamics.

CFM measures the volume of air flow, while HP quantifies the power output of a machine.

If it moves 100 CFM of air
At a pressure of 100 PSI (pounds per square inch)
With 90% efficiency

CFM	PSI	Efficiency	Horsepower
100	80	90%	12.50
200	90	85%	37.22
250	110	85%	45.49
300	100	80%	56.25
400	120	75%	75.00
500	95	80%	83.23
600	130	85%	108.08
700	100	90%	105.00
750	120	95%	133.57
800	150	90%	144.00
900	100	85%	117.65
1000	100	88%	159.77
1100	120	80%	178.57
1200	150	75%	192.00
1300	100	90%	192.86
1400	140	85%	216.47
1500	100	80%	248.12

CFM to HP Conversion Formula

HP = (CFM × PSI × 0.001406) / Efficiency

Where:

HP is Horsepower
CFM is Cubic Feet per Minute
PSI is Pounds per Square Inch
0.001406 is a conversion factor
Efficiency is the decimal representation of the system’s efficiency (e.g., 0.9 for 90%)

How do you convert CFM to HP?

To convert CFM to HP, follow these steps:

Determine the CFM of your system

Measure the operating pressure in PSI

Estimate the efficiency of your system (usually between 70-90%)

Apply the formula: HP = (CFM × PSI × 0.001406) / Efficiency

Let’s work through an example:

System CFM: 150

Operating Pressure: 90 PSI

Efficiency: 85% (0.85)

Plugging these values into our formula:

HP = (150 × 90 × 0.001406) / 0.85
HP = 22.33

A system moving 150 CFM at 90 PSI with 85% efficiency requires approximately 22.33 horsepower.

How many CFM is equal to 1 HP?

Pressure: 100 PSI
Efficiency: 100% (1.0)

Rearranging our formula to solve for CFM:

CFM = (HP × Efficiency) / (PSI × 0.001406)
CFM = (1 × 1.0) / (100 × 0.001406)
CFM ≈ 7.11

Approximately 7.11 CFM equals 1 HP.

How to calculate CFM into HP?

Measure CFM: Determine the airflow in cubic feet per minute
Determine PSI: Measure the operating pressure
Assess efficiency: Estimate your system’s efficiency
Apply the formula: HP = (CFM × PSI × 0.001406) / Efficiency
Round the result: HP is typically expressed to two decimal places

Example calculation:

CFM: 200
PSI: 120
Efficiency: 80% (0.8)

HP = (200 × 120 × 0.001406) / 0.8
HP = 42.18

In this scenario, 200 CFM at 120 PSI with 80% efficiency requires approximately 42.18 horsepower.

How much HP can 1000 CFM support?

The horsepower supported by 1000 CFM varies based on pressure and efficiency. Let’s calculate for different pressures assuming 90% efficiency:

At 50 PSI: HP = (1000 × 50 × 0.001406) / 0.9 HP ≈ 78.11

At 100 PSI: HP = (1000 × 100 × 0.001406) / 0.9 HP ≈ 156.22

At 150 PSI: HP = (1000 × 150 × 0.001406) / 0.9 HP ≈ 234.33

How much horsepower can CFM handle?

Generally, higher CFM values can handle more horsepower.

500 CFM: HP = (500 × 100 × 0.001406) / 0.85 HP ≈ 82.71

1000 CFM: HP = (1000 × 100 × 0.001406) / 0.85 HP ≈ 165.41

1500 CFM: HP = (1500 × 100 × 0.001406) / 0.85 HP ≈ 248.12

The amount of horsepower that CFM can handle is not a fixed value; it depends on the specific CFM value, operating pressure, and system efficiency.

Sources / References

U.S. Department of Energy. (2021). Improving Compressed Air System Performance. https://www.energy.gov/eere/amo/compressed-air-systems

Related Tools:

CFM to HP Calculator – CFM to Horsepower Conversion