The Inverter Sizing Calculator totals the running and surge demand of every connected appliance, applies a capacity margin, and recommends a continuous inverter rating along with the surge the unit must tolerate.
Inverter Sizing Calculator
Size an inverter from running and surge loads across several appliances, applying a capacity margin and power factor, and get a recommended standard rating plus DC input current.
Appliance loads (running / surge)
Design
DC side
Results
--
recommended inverter
--
surge required
Notes
About Inverter Sizing Calculator
Features
- Per-appliance running and surge watts
- Add as many appliance rows as needed
- Adjustable capacity margin
- Recommended continuous rating
- Surge requirement stated separately
How to Use
- Add a row per appliance with running and surge watts.
- Set the capacity margin.
- Read the recommended rating and the surge to confirm.
Examples
Example: 800 W plus 300 W running with an 1800 W combined surge and a 25% margin -> 1375 W required, so choose a 1500 W inverter able to deliver about 1800 W of surge.
Benefits
- Surge is sized explicitly, which is what actually trips undersized inverters
- The margin keeps the unit off its continuous limit
Frequently Asked Questions
What does this calculator do?
Size an inverter from running and surge loads across several appliances, applying a capacity margin and power factor, and get a recommended standard rating plus DC input current.
Is my data stored?
No. Everything runs in your browser; nothing is uploaded, saved or logged.