

CFM Calculator 


Side A in Feet 

Side B in Feet 

Total SqFt 

Ceiling Height in Feet 

Total Volume in CuFt 

Air Changes Per Volume 

Minutes 

CFM 


Round Duct 


Radius of Round Duct 

Diameter 

Area 

Length 

Volume 


Square or Rectangular Duct 


Side A in Inches 

Side B in Inches 

Area SqIn 

Length 

Volume CuIn 


Air Velocity in Round or Rectangular Duct 


Velocity Pressure in Inches W.G. 

Flow Velocity in Feet Per Minute 


Temperature Conversion (Celsius and Fahrenheit) 


Fahrenheit to Celsius 

Celsius 

Celsius to Fahrenheit 

Fahrenheit 


Fahrenheit to Rankine 


Fahrenheit 

Rankine 


Celsius to Kelvin 


Celsius 

Kelvin 


Charles Law (Jacques Charles 1787) 


Initial Temperature in Fahrenheit 

Final Temperature in Fahrenheit 

Initial Volume in CuFt 

Initial Temperature Rankine 

Final Temperature Rankine 

Final Volume 

Percent of Original Volume 


PSIG to PSIA 


PSIG 

PSIA 


PSIA to PSIG 


PSIA 

PSIG 


Boyle's Law (16271691) 


Initial Volume in CuFt 

Initial Pressure PSIG 

Final Pressure PSIG 

Initial Pressure PSIA 

Final Pressure PSIA 

Final Volume in CuFt 

Times Greater than Initial Vol 


Electric Charge 

Finding the Coulombs 


Current 

Time 

Coulombs 


Finding the Current 


Coulombs 

Time 

Current 


Ohms Law Solve for Resistance 


E Voltage 

I Amps or Current 

R Resistance 
Ohms Law Solve for Amperage or Current 


E Voltage 

R Resistance 

I Amps or Current 
Ohms Law Solve for Voltage 


I Amps or Current 

R Resistance 

E Voltage 


Ohms Law Solve for Power 


E Voltage 

I Amps or Current 

P Power 
Ohms Law Solve for Amperage or Current 


P Power 

E Voltage 

I Amps or Current 
Ohms Law Solve for Voltage 


P Power 

I Amps or Current 

E Voltage 
Ohms Law Solve for Power 


I Amps or Current 

R Resistance 

P Power 
Ohms Law Solve for Power Factor 


E Voltage 

I Amps or Current 

PF Power Factor 

P Watts (True Power) 

S Volt Amps (Apparent Power) 

Resistance 


Motor Speed 


Poles 

Hertz or Frequency 

Frequency (120 x Voltage) 

Speed in RPMs 


Motor Slip 


Synchronous Speed in RPM 

Rotor Speed 

Percent of Slip 