Generator Size Calculator
Not sure what size generator your home needs? Enter the appliances you want to power and we'll calculate the total wattage so you can buy with confidence.
Select your appliances
Check each appliance you want to power, then set the quantity.
700W / 2200W
1
1200W / 3600W
1
3800W / 10000W
1
800W / 2000W
1
4500W / 4500W
1
5400W / 6750W
1
1000W / 1000W
1
60W / 60W
1
150W / 150W
1
150W / 300W
1
50W / 50W
1
1500W / 1500W
1
750W / 1500W
1
500W / 1500W
1
How to use this calculator
- Always size for starting (surge) watts, not just running watts — motors briefly draw 2–3x their normal load.
- Add a 25% safety margin so your generator never runs at full capacity for long periods.
- If you plan to add appliances later, buy one size up rather than upgrading in a year.
- Inverter generators are quieter and safer for sensitive electronics like TVs and computers.
Common mistakes to avoid
- →Forgetting waste and overage. Most pros add 10–15% extra to cover offcuts, mistakes, and damaged material.
- →Measuring once. Always double-check critical dimensions before ordering — returns waste time and money.
- →Ignoring permits and codes. Check with your local building department before purchasing materials for any structural project.
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