Every product on this site with a heater or chiller publishes a wattage figure, and that number is all you need to estimate your own running cost — no guessing required. Here’s the math, with real examples.
The formula
Watts ÷ 1,000 × hours used × your electricity rate = cost per session
Your electricity rate is on your utility bill, usually stated per kWh. If you don’t know it, a reasonable placeholder for the U.S. is roughly $0.15-0.20/kWh, but your actual rate can vary significantly by region and time of use — check your bill for an accurate number.
Worked example: infrared sauna
A cabin drawing 2,250W for a 40-minute (0.67 hour) session: 2.25 kW × 0.67 hours × $0.17/kWh ≈ $0.26 per session
Used daily, that’s roughly $8/month — genuinely cheap, which is one of the real advantages of infrared over traditional heat.
Worked example: traditional sauna heater
A 6kW electric heater running for 45 minutes to heat up and hold temperature: 6 kW × 0.75 hours × $0.17/kWh ≈ $0.77 per session
Used 4 times a week, that’s roughly $13/month — still modest, but noticeably more than a comparable infrared session, which tracks with traditional heaters needing more power to heat the surrounding air rather than your body directly.
Worked example: cold plunge chiller
Cold plunge chillers don’t run only during your session — they cycle to maintain temperature between uses. A 0.25 HP chiller (roughly 450-500W) that’s actively cooling for an estimated 4-6 hours a day of total runtime: 0.475 kW × 5 hours × $0.17/kWh ≈ $0.40/day, or roughly $12/month
This is a rougher estimate than the sauna examples since chiller duty cycle depends heavily on ambient temperature, insulation, and how often the lid is open — treat it as a starting point, not a precise bill prediction.
What this doesn’t include
This calculation covers electricity only. It doesn’t include water (for cold plunges, if you’re not on a closed system), filter replacements, or wood fuel for a wood-burning heater — those are real ongoing costs on top of the electric estimate above.
Find your own numbers
Every product page on this site that has a published wattage or amperage figure gives you what you need to run this calculation yourself — check the Key Specifications section for “Power” or heater wattage, and plug it into the formula above with your own electricity rate for a real, personalized estimate rather than someone else’s assumption about your usage.