Inverter & Battery Calculator

Calculate suggested inverter VA and recommended battery AH from appliance loads, housing presets, and backup duration. Supports India, US, and EU quick-start configurations.

Total Load

340W

Suggested

850VA

Backup

4.5 Hrs

Recommended Battery

150 AH (12V)

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System Setup

Region, housing preset, and backup settings

Region

Quick Presets

1 hr6 hr12 hr

Appliance Management

Configure your load requirements

LED Bulb

Standard energy-efficient lighting

10W
4

Ceiling Fan

Standard 48-inch ceiling fan

75W
2

LED TV

32–43 inch LED television

80W
1

Wi-Fi Router

Home internet router

10W
1

Laptop Charger

Laptop power adapter

60W
1

Methodology and limitations

Last reviewed:

Methodology

Sums appliance wattage by quantity, applies power factor and safety margin for inverter VA, and divides energy demand by battery voltage and efficiency for AH. Results round up to standard market sizes.

Limitations

Motor startup surge, cable losses, battery aging, and temperature can affect real-world performance. Consult an installer for final sizing.

How to Use the Inverter & Battery Calculator

Calculate suggested inverter VA and recommended battery AH from appliance loads, housing presets, and backup duration. Supports India, US, and EU quick-start configurations.

Frequently Asked Questions

Add the wattage of all appliances running at the same time, divide by the power factor (typically 0.8 for mixed household loads), and apply a safety margin. The calculator rounds up to standard inverter sizes such as 600, 850, or 1000 VA.

Multiply total load in watts by desired backup hours, then divide by battery voltage and inverter efficiency. For conservative sizing, enable depth-of-discharge in advanced settings.

Watts measure real power consumed by appliances. VA (volt-amperes) is the apparent power an inverter must supply. Motors and inductive loads draw more VA than watts, so inverters are rated in VA.

12V systems are common for small homes and apartments. 24V and 48V suit larger loads because they reduce current and cable losses. Match your battery bank voltage to your inverter rating.

These are India-style housing presets (1, 2, or 3 bedroom-hall-kitchen units) that pre-fill typical appliance loads. US and EU presets use bedroom-based labels with region-appropriate wattages.

Yes. Refrigerators, air conditioners, and pumps can draw 2–3× their running watts at startup. Choose an inverter with adequate surge capacity beyond the steady-state VA shown here.

Disclaimer: The results provided by this calculator are for informational purposes only and are not guaranteed to be accurate or applicable to your specific circumstances. They do not constitute financial, legal, medical, or professional advice. You should not rely on these results as a basis for making decisions. Always consult a qualified professional. Daily Calcs disclaims any liability for errors, omissions, or outcomes resulting from the use of this calculator.