Heating & Cooling Calculators
Heating and cooling drive 40-50% of the average household energy bill — more than every other category combined. These four calculators help you compare systems, estimate running costs, and identify the cheapest way to keep your home comfortable across every season.
Heat Pump vs Gas Furnace
Compare annual heating costs between a heat pump and a gas furnace at your local energy rates.
Side-by-side verdictAir Conditioner Cost Calculator
Estimate the annual running cost of your AC unit based on BTU, SEER rating, and usage hours.
SEER rating explainedSpace Heater Cost Calculator
Calculate how much an electric space heater costs per hour, day, month, and year.
Simple and fastSmart & Programmable Thermostat Savings
Estimate annual savings from setting back your thermostat by a few degrees.
DOE-backed formulaWhy heating and cooling dominate your energy bill
Across most homes in the US, UK, Canada, and Australia, space heating and cooling account for the largest share of the annual energy bill — typically 40-50% for the average household, and higher in cold climates with electric resistance heating. Every other appliance category combined (refrigeration, water heating, lighting, electronics) usually adds up to less.
The two reasons heating and cooling cost so much: HVAC equipment runs for many hours each day during the heating and cooling seasons, and it moves or generates a lot of energy each hour. A central air conditioner can pull 3,000-5,000 watts continuously. A gas furnace can burn 40,000-100,000 BTU per hour. Even a small change in efficiency, runtime, or temperature setpoint multiplies into hundreds of dollars over a season.
That's why the savings from a heat pump upgrade, a SEER-rated AC replacement, or a smart thermostat are often the biggest single energy-savings actions a homeowner can take. The calculators above quantify each one with your actual rates and equipment.
Choosing the right calculator
→ Considering switching from gas to electric heating?
Start with the Heat Pump vs Furnace Calculator to see the annual running-cost difference using your local gas and electricity rates.
→ Trying to estimate AC running costs this summer?
Use the Air Conditioner Cost Calculator with your unit's BTU and SEER rating to project monthly and annual cost.
→ Considering a space heater for a single room?
Run the Space Heater Cost Calculator — most people underestimate just how expensive electric resistance heating is per hour.
→ Wondering if a smart thermostat is worth buying?
The Smart Thermostat Savings Calculator uses the US DOE 1%-per-degree rule to estimate your annual setback savings.
Heat pump efficiency at a glance
| System type | Typical efficiency | Heat delivered per kWh of electricity |
|---|---|---|
| Electric resistance (baseboard, space heater) | 100% | 1.0 unit |
| Air-source heat pump (cold-climate model) | COP 2.5-3.5 | 2.5-3.5 units |
| Air-source heat pump (mild climate) | COP 3.0-4.0 | 3.0-4.0 units |
| Ground-source (geothermal) heat pump | COP 3.5-5.0 | 3.5-5.0 units |
COP = Coefficient of Performance. A COP of 3.0 means the heat pump delivers 3 units of heat for every 1 unit of electricity it consumes. Source: US Department of Energy.
Common questions about heating and cooling costs
How much does it cost to heat a home with a heat pump vs a gas furnace?
A heat pump typically costs 30-50% less to run than a gas furnace in mild climates, but the comparison narrows in very cold regions. The exact difference depends on local electricity rates, gas rates, the heat pump COP (coefficient of performance), and the furnace AFUE rating. Our Heat Pump vs Furnace Calculator does the side-by-side maths for your inputs.
What is SEER and how does it affect AC running costs?
SEER stands for Seasonal Energy Efficiency Ratio. It measures how much cooling output (in BTU) an AC unit produces per watt-hour of electricity over a typical cooling season. A higher SEER means lower running costs. Replacing a SEER 10 unit with a SEER 16 unit cuts cooling costs by roughly 38%. Use our Air Conditioner Cost Calculator to see the difference for your unit.
How much can a smart thermostat actually save?
The US Department of Energy estimates 1% savings on heating and cooling costs for each degree of setback over 8 hours. So setting your thermostat back 7°F while you sleep and 7°F while at work could save around 14%. For a household spending $1,200 per year on heating and cooling, that is $168 in annual savings. ENERGY STAR-certified smart thermostats deliver these savings on average across users.
Are electric space heaters cheap to run?
No. Electric space heaters are inexpensive to buy but expensive to run because they convert electricity 1:1 into heat, with no efficiency multiplier. A 1,500W space heater running 8 hours per day costs around $2.04 per day or $61 per month at the US average rate. Heat pumps deliver 2-4× more heat per watt and are far cheaper for whole-room or whole-home heating.
What temperature should I set my thermostat to save money?
ENERGY STAR recommends 68°F in winter while awake (down to 60-65°F while asleep or away) and 78°F in summer while home (up to 85°F while away). Each degree closer to the outdoor temperature reduces your HVAC load. The savings are non-linear: the first few degrees of setback save more than the last few.
Data sources and methodology
Energy rate defaults are sourced from the EIA (US), Ofgem (UK), Natural Resources Canada, and the Australian Energy Regulator, refreshed quarterly. Equipment efficiency figures (SEER, AFUE, COP) come from ENERGY STAR and the US Department of Energy. Every calculator shows its formula, names its assumptions, and links to its sources — see our Methodology for the full standard.