Heat pump calculators that actually make sense
Size it, price it, and see your real savings in 60 seconds — built on US DOE & ENERGY STAR methodology, with no signup and no sales pitch.
Pick a calculator
Each one gives an instant, plain-English answer — then shows the math so you can trust it.
How to size and choose a heat pump
Buying a heat pump comes down to three questions: what size do I need, what will it cost, and will it actually save me money. Get the first one wrong and everything else suffers — an oversized unit short-cycles and wears out early, while an undersized one can't keep your home warm on the coldest nights.
The right size is set by your home's heat loss, not a number someone gave you at a barbecue. As a starting point, capacity scales with floor area and climate: a 1,800 sq ft home needs roughly 3–3.5 tons in a cold climate but only ~2.5 tons in a mild one. Insulation, ceiling height and air-sealing move that number up or down.
Bigger is not better. The goal is "just right," confirmed by a contractor's Manual J load calculation — our calculators get you a reliable starting estimate first.
The 4 steps
| Step | What to do | Tool |
|---|---|---|
| 1. Size | Find your BTU / tonnage from square footage + climate | Size calculator |
| 2. Price | Estimate installed cost by type, minus any rebates | Cost calculator |
| 3. Compare | Check running cost vs your current furnace | Savings calculator |
| 4. Verify | Find the balance point for cold-climate backup | Balance point |
One system, lower bills, no combustion
Heats and cools
A heat pump replaces both your furnace and your AC with a single, efficient unit.
2–4× efficient
It moves heat instead of burning fuel, delivering 250–400% efficiency (COP 2.5–4).
Rebates available
State and utility rebates can still cut hundreds to thousands off the installed price.
No on-site emissions
No gas burning means no carbon monoxide risk and a smaller carbon footprint.
What size heat pump do I need?
Jump to the guide for your home size — each shows the answer by climate zone.
Learn before you buy
Owning a heat pump
Transparent, not a black box
- Standards-based. Sizing uses climate-zone heat-load factors and equivalent full-load hours consistent with US DOE and ENERGY STAR guidance.
- We show the math. Every result lists the inputs and the breakdown, so you can sanity-check it — not just a number from nowhere.
- Honest about limits. These are rule-of-thumb estimates, not a replacement for a contractor's Manual J. We say so on every page.
- No data wall. No email, no account, no spam — just answers.
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