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Size a portable or standby generator from running and starting watts, and keep generator safety basics handy.

Coming to iPhone & Android

What it does

• Add the appliances you’ll run at the same time
• Totals running watts and adds the single largest starting surge
• Recommended size with 20% or 25% headroom
• Fuel runtime from your tank size and your generator’s own burn rate
• Safety Guide with CPSC/CDC basics, never locked
• Save load profiles, export a JSON backup, import, or reset

Planning estimates only. Always check nameplates and follow your generator’s owner’s manual. Home hookup needs a transfer switch installed by a licensed electrician.

• No ads
• No tracking
• Data stays on your phone
• Works offline
• All ages