Hardware tool
Generator Wattage Calculator
Estimate running watts, startup surge, and a safe generator size.
Runs in your browserResult
- Continuous load
- 3,200 W
- Startup peak
- 5,000 W
- Recommended generator
- 6,000 W
- Continuous current
- 26.7 A
Add appliance nameplate watts separately. Motors and compressors can have large startup surges; consult an electrician for transfer equipment.
How to use this generator wattage calculator
- Enter the rated capacity or power, expected load, losses, and safety allowance from the equipment labels or plan.
- Review the calculated totals, units, and assumptions. Check the inputs and units before relying on the result.
- Change one input at a time to compare another case, then copy or save the result you plan to use.
About this generator wattage calculator
Generator Wattage Calculator helps you estimate running watts, startup surge, and a safe generator size. The input and result appear together for easy comparison.
You can also use it to compare results after changing one input.
Example
Add the running watts of every device, include the largest motor startup surge, then add headroom before choosing a generator size.
Common uses
- → estimate running watts, startup surge, and a safe generator size
- → compare results after changing one input
- → save an estimate for planning or comparison