Cooling Tool
Estimate required airflow from IT heat load, inlet temperature and delta-T target, with altitude correction, cooling tons and ASHRAE operating class.
Quick Answer
Enter total IT load, inlet temperature, target delta-T, site altitude and design margin. The calculator estimates required CFM, m³/h, cooling tons, outlet temperature and whether the result stays inside the ASHRAE operating envelope.
Heat Load
Use practical planning values. Final design must be verified against ASHRAE TC 9.9 guidance, manufacturer data, containment design and a qualified mechanical/HVAC review.
Heat Load
Site Conditions
CFM = (kW × 3412) ÷ (1.085 × ΔT°F), where ΔT°F = ΔT°C × 1.8. Airflow is divided by the air-density ratio at altitude, and m³/h = CFM × 1.699. This is a simplified steady-state estimate.
Formula / Method
The calculator converts IT heat load to required airflow using the sensible-heat equation, applies the air-density correction for altitude, then reports metric airflow, cooling capacity, cooling tons and outlet temperature for the selected delta-T.
Required CFM = heat load ÷ (1.085 × ΔT°F) ÷ density ratio
Inputs
Use total IT load, inlet temperature, target delta-T, site altitude, design margin and a heat-to-cooling allowance for lighting and people.
Uses
Useful for server rooms, rack rows, CRAC/CRAH sizing checks, containment planning, high-density compute and early mechanical coordination.
FAQ
Air density drops with elevation, so each cubic metre of air carries less heat. The calculator divides airflow by the density ratio so more CFM is required to remove the same heat at altitude.
No. This is a planning calculator. Real rooms have bypass airflow, recirculation and hot-spot effects that require CFD analysis or physical testing per ASHRAE TC 9.9.
Many designs target 10–20 °C. ASHRAE A1/A2 commonly recommends ≤ 15 °C for IT equipment, but the right value depends on equipment, containment and the cooling system.
Learn More
Project
ITCOREOPS can support airflow checks, cooling load planning, rack power review, structured cabling, documentation, labeling and infrastructure handover.
Disclaimer
This calculator provides a simplified planning estimate only. It does not replace HVAC design, CFD analysis, manufacturer documentation, qualified engineering review, cooling redundancy design, site survey or professional inspection.
Workflow
Use this calculator before adding racks, servers, switches or UPS equipment to estimate required airflow, cooling capacity and ASHRAE operating class.
Support
For airflow checks, cooling load, rack power, structured cabling and operational infrastructure support, visit ITCOREOPS.
Feedback
Report display problems, calculation issues or suggestions for improving this calculator.
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