# Inverter Running Load Sizing Worksheet

Compare simultaneous running loads with an entered headroom allowance.

[Open this tool](https://whatson.pk/inverter-calculator/)

Category: Solar & Battery

An inverter needs to handle the loads running together, with separate attention to starting demand and equipment ratings.

List the simultaneous running appliances and choose a headroom allowance. Read watts and VA without assuming one replaces the other.

## Inputs and controls

* Running power allowance (%). Allowed range: 0 to 200
* Appliance
* Quantity (units). Allowed range: 1 to 10000
* Running power (W). Allowed range: 0 to 1000000
* Power factor (%). Allowed range: 0.01 to 100

## How to use

* Enter running power allowance.

* Add the entries in simultaneous running loads as separate rows. Include appliance, quantity, running power and power factor for each row.

* Select Calculate result. Read the returned values alongside the assumptions below before copying, exporting or acting on the result.


## Why use this tool

A visible load schedule provides a clearer sizing discussion than relying on a single appliance name or battery capacity.


## Before relying on the result

Assumes all entered loads run together. VA totals are conservative scalar sums. Check actual inverter W, VA, surge duration, temperature derating and manufacturer requirements separately.


## Tool limitations

Assumes all entered loads run together. VA totals are conservative scalar sums. Check actual inverter W, VA, surge duration, temperature derating and manufacturer requirements separately.

## Questions

### Does the worksheet approve an inverter model?

No. Check running ratings, surge duration, temperature derating and manufacturer requirements independently.

### What should I check before using Inverter Running Load Sizing Worksheet?

Check Running power allowance, Appliance, Quantity and Running power. Use the exact units shown beside the controls and replace any example values with your own inputs.

Source page last modified (UTC): 2026-10-01T18:56:36+00:00

This profile describes the tool. It does not execute it or supply a professional certification.