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SaunaCostUnofficial cost math

Methodology & assumptions

Formulas

  • kW = watts ÷ 1,000
  • hours = minutes ÷ 60
  • kWh per session = kW × (session hours + heat-up hours). Heat-up hours are 0 unless the heat-up toggle is on.
  • Cost per session ($) = kWh per session × electricity rate ($/kWh)
  • Cost per month ($) = cost per session × sessions per week × 52 ÷ 12
  • Cost per year ($) = cost per session × sessions per week × 52
  • Lifetime sessions = ownership years × sessions per week × 52
  • Amortized add-on $/session = purchase price ÷ lifetime sessions. If you enter a lifetime-session count, that count wins over years.
  • Year-1 total ($) = year-1 electricity + (amortized add-on × sessions in a year). That is the electricity bill plus the purchase dollars allocated to year 1.

Disclosed assumptions

  • Nameplate watts are treated as constant full power. Real heaters cycle; this overstates many bills and is the conservative bound.
  • No duty-cycle discount is applied. If you know a measured kWh from a plug meter, use that instead of nameplate math.
  • Heat-up is optional and, when enabled, is also billed at full nameplate power for the heat-up minutes you enter.
  • Monthly cost uses 52 weeks / 12 months (≈ 4.333 weeks), not a 4-week calendar month.
  • The default rate is a U.S. residential national proxy. Your tariff, taxes, demand charges, and time-of-use periods are not modeled.
  • Purchase amortization is straight-line over years or total sessions. It is not depreciation, financing, or resale value.
  • Cabin lights, audio, fans, and 12 V controls are omitted unless you fold them into watts.
  • SaunaCost is unofficial and not affiliated with any sauna OEM, dealer, or utility.

Default electricity rate

18.34¢/kWh ($0.1834/kWh) from U.S. Energy Information Administration, Electricity Monthly Update — U.S. residential average revenue per kWh, June 2026. Average revenue per kWh is a national proxy, not your tariff. Replace the default with the supply charge on your bill.

Sources

Disclaimer

SaunaCost is an independent planning tool. It is not affiliated with Peak Saunas, SaunaAdviser, or any cabin or heater manufacturer. Estimates are not a utility bill, not financial advice, and not a statement about health, “detox,” or therapeutic effect. If your unit’s rating plate disagrees with a preset, trust the plate.