About

Most power and cooling calculators are built by manufacturers, and they are free for a reason: they exist to route you toward a product line. The math is usually fine. What they leave out is everything that makes a real deployment awkward.

This one is vendor-neutral and built around the constraints that actually bite. Nameplate ratings overstate draw. Production racks are continuous loads, so the 80% derate is a hard ceiling rather than a guideline. Ambient temperature quietly destroys battery life long before it trips a thermal alarm. Per-rack density, not room total, is what decides whether air cooling still works.

It also shows its work. Every formula and constant is published on the methodology page, with the standard it comes from, so you can check the result or hand it to someone who will.

Use it to frame a problem, sanity-check a vendor quote, or find out early that a plan does not fit the circuits you have. Then get the design engineered and stamped.