Formula & worked example
COPh=Qhot/W; COPCarnot=Thot/(Thot−Tcold), kelvin.
A heat pump delivering 10 kW from 2.5 kW input has COP 4.0.
Heating & HVAC engineering calculator · Updated Sep 17, 2026
Heat Pump COP Calculator — Heating Output, Power & Carnot COP
Calculate heating COP from delivered heat and electrical input, with ideal Carnot heating COP and percentage of Carnot.
Inputs
Live result
Heating COP 4
Electrical input per 10 kW heat 2.5 kW
Carnot heating COP 7.95375
Fraction of Carnot 50.290743%
Assumptions & limits
- Electrical input should include the equipment boundary you intend to compare.
- Carnot COP is a theoretical reversible ceiling, not a seasonal rating.
Frequently asked questions
What does this Heat Pump COP Calculator calculate?
Calculate heating COP from delivered heat and electrical input, with ideal Carnot heating COP and percentage of Carnot.
What units are supported?
Inputs state their unit basis and results include practical SI and US customary equivalents where useful, so the calculation can be checked against field data and equipment schedules.
Can I use this for final equipment selection?
Use it for transparent first-pass sizing and engineering cross-checks. Final selections should use measured conditions, manufacturer performance data and applicable codes or design standards.