How long will your inverter battery last? What battery capacity do you need for your appliances?

AmpPlan is an inverter battery calculator that helps you estimate battery backup time, required battery size, inverter size and charging time. Plan your home power backup with clear results and practical assumptions.

ESTIMATE BATTERY BACKUP TIME
Use the battery backup calculator to estimate how long your battery may power your selected load. View backup time in hours and minutes so it is easier to compare your options.

FIND THE BATTERY CAPACITY YOU NEED
Choose a target backup time and estimate the required battery capacity in amp-hours (Ah). Compare your power needs before selecting an inverter battery.

PLAN YOUR INVERTER SIZE
Estimate an inverter size for your running load and appliance startup demand. Review the assumptions behind the result instead of relying on a single unexplained number.

BUILD YOUR APPLIANCE LOAD
Enter total watts directly or use the appliance load calculator to combine common appliances and quantities. See how a different load changes your backup-power plan.

ESTIMATE CHARGING TIME
Estimate how long your battery may take to charge using the inputs and assumptions in your plan.

COMPARE AND SAVE PLANS
Explore What-If scenarios, compare possible changes and save plans locally on your device. Use electrical converters when working with supported units.

SIMPLE WHEN YOU NEED IT
Start with straightforward questions in Simple mode. Use Advanced options when you need more control over the calculation assumptions.

OFFLINE CALCULATIONS. NO ACCOUNT REQUIRED.
Core calculations work offline. Saved plans stay on your device, with no account or cloud storage required.

ENGLISH AND HINDI
Use AmpPlan in English or Hindi, with light and dark appearance options.

IMPORTANT
AmpPlan provides planning estimates, not electrical installation advice. Actual backup and charging performance vary with battery age, chemistry, temperature, wiring, inverter efficiency, appliance startup demand and manufacturer specifications. Confirm equipment selection and installation with a qualified professional.