Terms of Use

Last updated: October 2026.

Estimates only

The calculators give rough estimates from typical values and published rules of thumb. Real appliances, homes and climates vary. Always check equipment nameplates and manufacturers' specifications before you buy or connect anything.

Not professional advice

Nothing on this site is electrical, plumbing, HVAC, engineering or safety advice for your situation. Generator connections, transfer switches, gas lines, venting, refrigerant work and new circuits must be done by licensed professionals under local codes and permits. Never run a generator indoors or backfeed a house through an outlet.

No warranty

The site is provided "as is", without warranties of any kind. To the extent the law allows, we are not liable for any loss or damage from using it or relying on its results.

Affiliate disclosure

Some links are affiliate links: if you buy through them we may earn a commission, at no extra cost to you. As an Amazon Associate we earn from qualifying purchases. Links are chosen by the size you calculate, not by commission, and we don't publish ratings or reviews.

Brands

Brand and program names (including ENERGY STAR) are used only to describe products and sources. We are not affiliated with or endorsed by any manufacturer, retailer or government agency.