Device Runtime Calculator
Calculate how long your electronic device will run on battery power based on battery capacity and power consumption.
Runtime Results
How to Use This Calculator
- Enter your device's battery capacity in milliamp-hours (mAh)
- Input the device's operating voltage (typically 3.7V for lithium-ion)
- Enter the device's power consumption in watts
- Adjust battery efficiency if known (default is 85%)
- Click "Calculate Runtime" to see results
Finding Device Specifications
- Battery Capacity: Check device specifications or battery label
- Power Consumption: Use manufacturer specs or power meter
- Voltage: Usually 3.7V for phones/tablets, varies for laptops
Frequently Asked Questions
How accurate is this device runtime calculator?
The calculator provides estimates based on theoretical calculations. Actual runtime may vary due to factors like screen brightness, wireless connectivity, background apps, temperature, and battery age. Results are typically within 10-20% of actual performance under normal conditions.
What factors affect device battery runtime?
Runtime is affected by screen brightness, processor usage, wireless connections (WiFi, Bluetooth, cellular), background applications, temperature, battery health, and power management settings. Heavy usage like gaming or video streaming significantly reduces runtime compared to standby mode.
How do I find my device's power consumption?
Check manufacturer specifications, use built-in battery monitoring tools, or use external power meters. For smartphones, typical consumption ranges from 1-3W during normal use. Laptops typically consume 15-45W depending on model and usage. Gaming and video streaming increase consumption significantly.
Why is battery efficiency important in runtime calculations?
Battery efficiency accounts for energy losses during discharge due to internal resistance, heat generation, and voltage conversion. Lithium-ion batteries typically operate at 85-95% efficiency. Lower efficiency means less usable energy and shorter runtime than theoretical calculations suggest.
How can I extend my device's battery runtime?
Reduce screen brightness, disable unnecessary wireless connections, close background apps, use power saving modes, lower screen refresh rates, disable location services when not needed, and keep the device at moderate temperatures. Regular software updates often include battery optimization improvements.