Inverter Size Calculator
Calculate optimal inverter capacity based on your appliance load requirements
Appliances & Load
Inverter Configuration
Inverter Requirements
Load Analysis
Cost & Specifications
Appliance Status
✅ Simultaneous Use
⏱️ Occasional Use
Quick Summary
Load Distribution
How Inverter Size Calculation Works
Load Calculation
Total connected load: Sum of all appliance loads = 2,625W
Simultaneous load: Only appliances marked for simultaneous use = 625W
Safety Margin & Sizing
Inverter size = Simultaneous load + Safety margin = 625W + 25% = 782W
Cost & Efficiency
Pure-sine inverter cost: 782W × ₹15/W = ₹11,730
Load Factor Analysis
Load factor = Simultaneous load ÷ Total connected load = 625W ÷ 2,625W = 23.81%
Pro Tips for Inverter Selection
Inverter Type Selection:
- • Pure Sine Wave: Better for sensitive electronics
- • Modified Sine: Lower cost, basic appliances only
- • Safety Margin: 25-30% recommended for future loads
- • Consider starting surge of motors (2-3x rated power)
Load Management:
- • Mark high-power appliances as non-simultaneous
- • Use timers to prevent simultaneous operation
- • Consider load shedding for critical applications
- • Plan for seasonal load variations
Your System Recommendation:
The Inverter Size Calculator is for anyone setting up a home power backup or solar system who needs to know what inverter capacity (in watts or kVA) to buy. List your appliances, mark which ones run at the same time, and it calculates the recommended inverter size with a safety margin for startup surges.
Inverter Size Calculator - FAQs
How do you decide what inverter size (watts/kVA) I need?
We sum the wattage of appliances you mark as "simultaneous", add your chosen safety margin (default 25%), then convert the wattage to kVA using an assumed power factor of 0.8.
Why do I need to mark appliances as "simultaneous" or not?
Only appliances that run at the same time load the inverter together. Appliances used occasionally, like a washing machine, don't need to be added to the peak load, which keeps the recommended inverter size realistic.
Why include a safety margin?
Motors and compressors draw a brief surge (2-3x rated power) at startup, and a margin also leaves headroom for adding appliances later, so 25-30% extra capacity is commonly recommended.
Pure sine wave vs modified sine wave — which should I choose?
Pure sine wave inverters cost more (around ₹15/watt vs ₹10/watt) but are safer for sensitive electronics and run at higher efficiency (about 95% vs 85%). Modified sine wave is only suitable for basic resistive loads.
Are the wattage and cost figures here exact?
They are typical estimates for planning purposes — actual appliance wattages and inverter prices vary by brand and model, so confirm with a supplier before purchase.
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