Generator Wattage Calculator
Compare continuous and starting load scenarios using your own appliance wattages and an explicit allowance.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Sum quantity times running watts for every appliance. For one-at-a-time starting, add the largest extra startup draw. For simultaneous starting, add all entered starting wattages. Apply your allowance to the selected load scenario.
One-start load=Σ(q×running W)+max(starting W−running W)
Worked example
Running loads totaling 690 W with a largest startup increment of 1050 W give a one-start load of 1740 W before allowance.
Assumptions and input details
Starting watts mean total startup draw, not extra watts. No appliance ratings are looked up. This arithmetic does not determine generator suitability, surge duration, power factor, wiring, installation or fuel needs.
References: Honda: running and starting wattage
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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