Use YUGUANG’s Battery Life Calculator to estimate how long your device can operate based on battery capacity and average current consumption. By entering the nominal battery capacity and the load’s average current draw, the calculator predicts the expected battery runtime. Battery capacity is typically measured in amp-hours (Ah) or milliamp-hours (mAh), while watt-hours (Wh) may also be used in some applications. This tool provides a quick and practical way to evaluate battery performance for electronic devices and power-consumption planning.
Enter your parameters below to calculate results.
Battery life refers to the duration a device can operate before its battery requires recharging. Calculating this effectively requires understanding the relationship between capacity, consumption, and efficiency factors.
Before using the calculator, it is helpful to understand the units involved:
While no battery lasts forever, you can estimate the approximate runtime using this standard formula:
Where:
Calculated results are estimates. Real-world performance depends on several variables:
The following table provides estimated capacities for common battery types to help you estimate if you don't have the exact data sheet.
| Battery Size | Chemistry | Estimated Capacity (mAh) | Notes |
|---|---|---|---|
| AAA | Alkaline | 1200 | Standard remote batteries |
| NiMH | 800 – 1000 | Rechargeable | |
| AA | Alkaline | 2700 | Standard household use |
| Lithium (Rechargeable) | 3000 | High drain devices | |
| NiMH | 1700 – 2900 | ||
| C | Alkaline | 8000 | Medium drain |
| NiMH | 4500 – 6000 | ||
| D | Alkaline | 12000 | High capacity flashlights |
| NiMH | 2200 – 12000 | Wide variance in quality | |
| Lithium-Primary (3.6V) | 19000 | Industrial use | |
| 9V (PP3) | Alkaline | 565 | Smoke detectors |
| Lithium-Primary | 1200 | Long-life applications | |
| NiMH | 175 – 300 | ||
| 6V Lantern | Alkaline | 26000 | Heavy duty lighting |
| CR2032 | Lithium-Primary (3V) | 240 | Coin cell (BIOS, watches) |
| CR2016 | Lithium-Primary (3V) | 90 | Thinner coin cell |
| 1/10 D | Lithium-Primary (3.6V) | 1000 | Specialized industrial |
| 4 Farad Cap | Capacitor | ~1 mAh | Equivalent @ 1mA drain/1V drop |