Server room cooling calculator
Turn your IT load into a cooling requirement in seconds. Enter the kW (or watts) your equipment draws and see the heat output in BTU/hr and tons of refrigeration, plus a recommended installed capacity with a design margin and an N+1 spare unit.
Your IT load
Recommended installed cooling with 20% margin and an N+1 spare unit: ≈ 40,946 BTU/hr. Almost 100% of IT power becomes heat, so heat (kW) ≈ IT load (kW).
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Power in equals heat out
Servers convert virtually all the electricity they consume into heat, so the heat your cooling must remove is essentially the same as the power your UPS and PDUs deliver. Undersized cooling is one of the most common causes of thermal shutdowns and shortened hardware life in small server rooms and comms cupboards.
The exact conversion is 1 kW = 3,412.142 BTU/hr, and 1 ton of refrigeration = 12,000 BTU/hr. We add your chosen margin for non-IT heat (lighting, people, solar gain) and an N+1 spare so a single cooler failure does not take the room down. For a full room or data-centre build, our data centre team can design the power and cooling together.
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Server room cooling — common questions
How do I calculate server room cooling requirements?
Almost all the electrical power your IT equipment draws is converted to heat, so the heat load in kW is approximately equal to the IT load in kW. Convert to BTU/hr by multiplying kW by 3,412.142, or to tons of refrigeration by dividing the BTU/hr by 12,000. A 5 kW IT load produces about 17,061 BTU/hr, or roughly 1.42 tons. Add a margin and redundancy on top — this calculator does all of that.
How many BTU do I need per kW of IT load?
1 kW of IT load produces 3,412.142 BTU/hr of heat (an exact physical conversion). So a 10 kW room needs at least 34,121 BTU/hr of cooling before margin. In practice you add a design margin (15–25%) for door openings, lighting and people, and an N+1 spare unit so the room stays cool if one cooler fails.
What is a "ton" of cooling?
A ton of refrigeration equals 12,000 BTU/hr — historically the cooling from melting one ton of ice in 24 hours. Air-conditioning and CRAC/CRAH units are often rated in tons or kW, so the calculator shows both BTU/hr and tons to match whatever the cooling supplier quotes.
Should I add redundancy to cooling?
Yes. For any room that must stay online, size cooling as N+1 — enough units that the load is still covered if one fails for service or fault. This calculator shows the IT heat, your design margin and the N+1 spare as a single recommended installed capacity, so a 5 kW room is provisioned well above its bare 17,061 BTU/hr.
Does heat output equal power consumption?
For IT equipment, effectively yes. Servers do not store energy, so virtually 100% of the electricity they consume leaves as heat. That is why heat load (kW) ≈ IT load (kW), and why your cooling must remove as much power as your UPS and PDUs deliver. A small amount of energy leaves as fan airflow and acoustic noise, but it is negligible for sizing.
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