Solar Panel Calculator

A battery life calculator estimates how long a battery will last based on its capacity, device power consumption, and usage patterns.

Battery capacity is the total energy stored, measured in milliamp-hours (mAh) or amp-hours (Ah).

Voltage is the electrical potential difference, measured in volts (V), determining the battery's power output.

Watt-hour measures total energy: Wh = Voltage × Amp-hours. It combines capacity and voltage.

Current draw is the amount of current the device consumes, measured in milliamps (mA) or amps (A).

Power consumption is the rate of energy use, measured in watts (W): Power = Voltage × Current.

Discharge rate is how quickly the battery loses charge, often expressed as C-rate (capacity per hour).

DoD is the percentage of battery capacity that has been used. 80% DoD means 80% consumed.

SoC is the remaining capacity percentage. 50% SoC means half the capacity remains.

Cycle life is the number of charge-discharge cycles before capacity significantly degrades.

Li-ion is a rechargeable battery type with high energy density, used in phones, laptops, and EVs.

Lead-acid is a rechargeable battery type used in cars, UPS systems, and solar storage.

Alkaline is a primary (non-rechargeable) battery type used in remote controls, clocks, and toys.

Nickel-metal hydride is a rechargeable battery type used in cameras, hybrid cars, and power tools.

Battery efficiency is the ratio of energy output to energy input during charging/discharging.

Enter battery capacity (mAh) and device current draw (mA). The calculator computes hours = mAh / mA.

Input battery capacity, voltage, and device power consumption. Click "Calculate" for estimated runtime.

Enter mAh capacity and mA current draw. Battery life = mAh / mA hours.

Enter Wh capacity and W power draw. Battery life = Wh / W hours.

Enter voltage and capacity. Convert between mAh and Wh as needed.

Enter phone battery capacity (typically 3000-5000 mAh) and usage patterns.

Enter laptop battery Wh capacity and power adapter wattage.

Enter tablet battery capacity and typical usage current.

Enter camera battery mAh and average current draw.

Enter tool battery voltage and amp-hour capacity.

Enter EV battery kWh capacity and average consumption (kWh/100mi).

Enter battery bank capacity and daily load requirements.

Enter UPS battery capacity and connected load wattage.

Enter remote battery capacity and typical usage.

Enter device sleep/wake current and duty cycle.

Enter wearable battery capacity and usage patterns.

Enter drone battery capacity and flight current draw.

Enter RC battery capacity and motor current draw.

Enter battery capacity and LED current draw.

Enter device battery capacity and operating current.

Understanding battery life helps plan usage, prevent unexpected shutdowns, and optimize performance.

Capacity determines how much energy is available, directly affecting runtime.

Lower current draw extends battery life. Understanding consumption helps optimize usage.

Voltage affects power output and compatibility with devices.

Shallow discharge extends battery life. Deep discharge can damage batteries.

Mobile devices depend on battery life for usability throughout the day.

EV range depends on battery capacity and efficiency.

Battery storage capacity determines backup duration during outages.

UPS runtime determines how long equipment stays powered during outages.

IoT devices often run on batteries for years, requiring efficient power management.

Yes. Enter the device's power requirements and battery capacity.

Yes. Calculate for Li-ion, lead-acid, alkaline, NiMH, and other types.

Yes. Enter any voltage for capacity and power calculations.

Yes. Enter any mAh, Ah, or Wh capacity.

Yes. Enter any mA or A current consumption.

Yes. Enter average current for mixed usage scenarios.

Yes. Calculate combined capacity for parallel configurations.

Yes. Calculate total voltage for series configurations.

Yes. Account for capacity reduction at extreme temperatures.

Yes. Account for capacity degradation over battery life.

Yes. Calculate capacity at different C-rates.

Yes. Calculate time to charge based on charger output.

Yes. Calculate total energy used over time.

Yes. Calculate operating cost based on electricity rates.

Yes. Estimate emissions based on energy consumption.

Yes. The calculator uses standard formulas for accurate runtime estimates.

Yes. The battery life calculator is completely free with no registration.

Yes. All calculations are performed in your browser with no data transmitted.

Yes. The calculator implements standard battery calculations.

Yes. The calculator helps consumers understand device battery life.

Yes. The calculator is regularly updated to ensure accuracy.

Yes. The calculator works on smartphones, tablets, and desktop computers.

The calculator provides estimates. Actual battery life depends on usage conditions.

Yes. Engineers use similar calculations for battery system design.

Yes. The calculator teaches battery concepts and energy calculations.

mAh measures charge capacity. Wh measures energy capacity. Wh = mAh × V / 1000.

Capacity is total energy stored. Runtime is how long that capacity lasts.

Different chemistries have different energy densities, cycle lives, and characteristics.

Series increases voltage. Parallel increases capacity.

Rated is manufacturer specification. Actual varies with conditions and age.

C-rate is relative to capacity. Current is absolute measurement.

DoD is percentage used. SoC is percentage remaining. DoD + SoC = 100%.

Battery life is runtime per charge. Cycle life is total charge cycles.

Battery calculator estimates runtime. Power calculator determines consumption.

Battery is one type of energy storage. Others include capacitors, flywheels, and pumped hydro.

Calculate when choosing devices, planning usage, or designing battery systems.

When comparing devices with different battery specifications.

When planning device usage during travel without charging access.

When ensuring devices last through work shifts or meetings.

When planning backup power duration for critical equipment.

The Solar Panel Calculator uses verified mathematical formulas processed entirely in your browser. Calculator inputs and results are never sent to external servers. We do use Google Analytics and AdSense for standard website operation — see our Privacy Policy for details.

Yes. All calculations happen locally in your browser. We never store, transmit, or log any input data you enter into the calculator.

Double-check that all inputs are valid numbers within reasonable ranges. If you believe there is an error, please contact us with your input values and we will investigate.