About this tool
The SEER / SEER2 Cooling Cost Calculator is a free, in-browser tool that estimates how much electricity your air conditioner or heat pump uses for cooling each year and what a higher-efficiency unit would save. Annual cooling energy is capacity (BTU/hr) × annual runtime hours ÷ (SEER × 1000), where capacity equals tons × 12,000 BTU/hr, and the annual cost is that kWh figure times your electricity rate.
Everything is computed locally in your browser, so your usage and rate never leave your device. SEER (Seasonal Energy Efficiency Ratio) and the newer SEER2 rating from the U.S. DOE's 2023 test procedure both work here — SEER2 is roughly SEER × 0.95, and the tool converts whichever standard you pick so the divisor is consistent. Cooling runtime varies enormously by climate, so the calculator offers mild (≈800 h), moderate (≈1200 h), and hot (≈1800 h) presets that you can override with your own hours.
Enter a comparison SEER to see the head-to-head annual cost and the dollars saved by upgrading, and add the equipment cost to get a simple payback in years (upgrade cost ÷ annual savings). Because savings scale with the difference of the reciprocals of the two ratings, most of the benefit comes from the first few SEER points; going from 14 to 18 SEER saves far more per point than going from 20 to 24. Results are estimates — real bills depend on weather, thermostat habits, and duct and installation quality.