SCFM to CFM Calculator
SCFM to ACFM Calculator
Need to convert SCFM to CFM? This calculator can help. By entering specific parameters, you can easily find the CFM from SCFM.
What is SCFM to CFM?
SCFM stands for Standard Cubic Feet per Minute, a measure of airflow standardized to specific temperature and pressure. CFM, or Cubic Feet per Minute, is the actual airflow at operating conditions. Converting SCFM to CFM adjusts for realworld conditions like temperature and pressure.
How to Use the Calculator
Enter SCFM:

 Example: SCFM = 150
Enter Actual Temperature (°F):

 Example: 72
Enter Actual Pressure (psi):

 Example: 14.4
Enter Barometric Pressure (psi):

 Example: 14.7
Enter Relative Humidity:

 Example: 0.36
Click “Calculate” to get the CFM.
Formula
The formula to convert SCFM to CFM is:
$\text{CFM} = \text{SCFM} \times \frac{P_s – (RH_s \times P_{vs})}{P_b – (RH_a \times P_{va})} \times \frac{T_a}{T_s} \times \frac{P_b}{P_a}$
Variables
Variable  Description 

SCFM  Standard Cubic Feet per Minute 
$T_a$  Actual Temperature (°F + 460) 
$P_a$  Actual Pressure (psi) 
$P_b$  Barometric Pressure (psi) 
$RH_a$  Relative Humidity 
$P_{va}$  Vapor Pressure at Actual Temp (psi) 
$T_s$  Standard Temperature (°F + 460) 
$P_s$  Standard Pressure (psi) 
$RH_s$  Standard Relative Humidity 
$P_{vs}$  Standard Vapor Pressure (psi) 
Calculation Examples
Example 1
Input:
 SCFM = 150,
 Temp = 72°F,
 Actual Pressure = 14.4 psi,
 Barometric Pressure = 14.7 psi,
 Relative Humidity = 0.36
Calculation:
1 . Convert temperatures to Rankine (°F + 460):


 $T_a = 72 + 460 = 532$
 $T_s = 68 + 460 = 528$

2. Using standard values:
$P_s = 14.7$ psi, $RH_s = 0.36$, $P_{vs} = 0.3391$
3. Calculate vapor pressure at actual temp ($P_{va}$):
$P_{va} = 0.0145038 \times 6.11 \times 10^{(7.51 \times 22.22 / (237.7 + 22.22))}$
$P_{va} \approx 0.021$
4. Calculate CFM: $\text{CFM} = 150 \times \frac{14.7 – (0.36 \times 0.3391)}{14.7 – (0.36 \times 0.021)} \times \frac{532}{528} \times \frac{14.7}{14.4}$ $\text{CFM} \approx 152.3$
5. Result: 152.3 CFM
Example 2
Input:
 SCFM = 200,
 Temp = 80°F,
 Actual Pressure = 15 psi,
 Barometric Pressure = 14.7 psi,
 Relative Humidity = 0.4
Calculation:
 Convert temperatures to Rankine (°F + 460):


 $T_a = 80 + 460 = 540$
 $T_s = 68 + 460 = 528$

2. Using standard values:
$P_s = 14.7$ psi, $RH_s = 0.36$$P_{vs} = 0.3391$
3. Calculate vapor pressure at actual temp ($P_{va}$):
$P_{va} = 0.0145038 \times 6.11 \times 10^{(7.51 \times 26.67 / (237.7 + 26.67))}$
$P_{va} \approx 0.024$
4. Calculate CFM: $\text{CFM} = 200 \times \frac{14.7 – (0.36 \times 0.3391)}{14.7 – (0.4 \times 0.024)} \times \frac{540}{528} \times \frac{14.7}{15}$ $\text{CFM} \approx 204.7$
5. Result: 204.7 CFM
I hope you find the SCFM to CFM Calculator helpful. How was your experience? If you encounter any issues, please report them on our “Report an Error” page. Your feedback is valuable to us.