Generator Size Calculator
This generator size calculator lets you input the individual wattage requirements of all the appliances, tools, and equipment you intend to power simultaneously — including both running and starting watts — to arrive at an estimate of the minimum generator capacity needed. It typically includes fields for listing devices, their power demands, and any additional safety margin to ensure the generator can handle peak loads. The calculator then totals these inputs and recommends a generator size in watts or kilowatts, helping you make an informed decision quickly, whether you’re sizing for home backup, jobsite equipment, or larger commercial power requirements.
How Does a Generator Size Calculator Work?
This generator size calculator lets you input the individual wattage requirements of all the appliances, tools, and equipment you intend to power simultaneously — including both running and starting watts — to arrive at an estimate of the minimum generator capacity needed. It typically includes fields for listing devices, their power demands, and any additional safety margin to ensure the generator can handle peak loads. The calculator then totals these inputs and recommends a generator size in watts or kilowatts, helping you make an informed decision quickly, whether you’re sizing for home backup, jobsite equipment, or larger commercial power requirements.
Using a purpose-built generator size calculator helps you avoid common mistakes like underestimating starting wattage or overlooking key appliances and tools, giving you a reliable estimate of the generator capacity you actually need. It provides clarity on total power requirements, saves you time compared to manual calculations, and helps you make cost-effective choices by matching generator capacity closely to your actual load requirements. This structured approach makes it easier to plan for emergencies, events, or ongoing power needs, so you can select a generator that delivers dependable performance without wasting fuel or spending more than necessary.
Why Generator Sizing Matters
Using a purpose-built generator size calculator helps you avoid common mistakes like underestimating starting wattage or overlooking key appliances and tools, giving you a reliable estimate of the generator capacity you actually need. It provides clarity on total power requirements, saves you time compared to manual calculations, and helps you make cost-effective choices by matching generator capacity closely to your actual load requirements. This structured approach makes it easier to plan for emergencies, events, or ongoing power needs, so you can select a generator that delivers dependable performance without wasting fuel or spending more than necessary.
Overview
ArcSite’s generator size calculator helps you choose a generator with the correct rating for your household. Simply enter the wattage of your devices along with the number of devices. Our tool also lets you add custom devices, outputting a more accurate generator rating.
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FAQs
Add up the wattage requirements for all your appliances in your household to calculate the size of the generator that you must install.
Starting or surge wattage is the temporary wattage that your generator must provide to start an appliance whereas running wattage keeps your appliance running.
Generators run on various sources, including fuels such as diesel and gasoline as well as renewable sources like hydrogen and solar energy.
