Inverter Sizing Calculator
Find the right inverter size for your appliances. We calculate both running watts and surge watts.
Quick Scenarios
Select Your Devices
❄️
Refrigerator
150W
Surge: 600W
🧊
Freezer
100W
Surge: 400W
🔵
Well Pump
750W
Surge: 2250W
📺
LED TV
100W
💻
Laptop Charger
65W
🍲
Microwave
1000W
Surge: 1500W
☕
Coffee Maker
800W
❄️
Portable AC
500W
Surge: 1500W
🔥
Space Heater
1500W
🫧
Washing Machine
500W
Surge: 1500W
🍽️
Dishwasher
1200W
Surge: 1800W
🌀
Ceiling Fans
75W
Surge: 150W
🛁
Water Heater
3000W
🚗
Garage Door Opener
500W
Surge: 1500W
💧
Sump Pump
800W
Surge: 2400W
Add Custom Device
Leave blank for 3× running watts
Inverter Sizing Tips
Always add a 20% safety margin to your total running watts
Surge watts are critical for motors (refrigerators, pumps, AC units)
Pure sine wave inverters are best for sensitive electronics
Consider future expansion when sizing your inverter
Match your inverter to your battery voltage (12V, 24V, 48V)