Inverter Size Calculator
Calculate the recommended inverter size for your load, including a safety margin.
Calculate
Enter your values below.
Result
Recommended inverter size
0
Formula used
Inverter size = Load (W) × Safety factor
Example: 800 W load with a 1.25 safety factor → recommended inverter ≈ 1,000 W.
How to use this calculator
- Enter Total load (watts), Safety factor (e.g. 1.25 = 25% margin).
- Press Calculate to see your result instantly.
FAQ
Frequently asked questions
Why add a safety margin?
To handle startup surges (especially from motors) and avoid running the inverter at its absolute limit continuously.
What safety factor should I use?
1.2-1.3 (20-30% margin) is common for general use; motor-heavy loads may need even more headroom for startup surge.
Should I add up all my devices' wattage?
Yes — sum the running wattage of everything you plan to power simultaneously.
Does this account for surge/starting wattage separately?
Not directly — check your highest-surge device's starting wattage and ensure the inverter's surge rating covers it too.