Data Center CFM per kW Calculator
Rack airflow from IT load and delta T.
Enter your values
ⓘ Live results
Results
- CFM per kW
- 158
- Airflow per rack
- 1,264 CFM
- Total room airflow
- 12,637 CFM
- Total IT load
- 80 kW
- Cooling required
- 22.7 tons
Quick answer
IT equipment needs roughly 126 CFM per kW at a 20°F rise, scaling inversely with the delta T you design for.
CFM = kW x 3412 / (1.08 x ΔT °F)
How to use the Data Center CFM per kW Calculator
- 1Enter the average IT load per rack in kW.
- 2Choose the delta T across the equipment — 20°F is common, 30°F for containment designs.
- 3Make sure the CRAC units can deliver the total airflow, not just the tonnage.
Worked example
Using the values the calculator loads with:
Inputs
- IT load8 kW
- Temperature rise20 °F
- Number of racks10
Results
- CFM per kW158
- Airflow per rack1,264 CFM
- Total room airflow12,637 CFM
- Total IT load80 kW
- Cooling required22.7 tons
Frequently asked questions
Why does delta T matter so much?
Raising delta T from 20 to 30°F cuts required airflow by a third, saving large amounts of fan energy.
Containment?
Hot or cold aisle containment prevents recirculation and lets you run higher supply temperatures.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.