Battery Life Estimator

• Battery life estimator
• Enter battery capacity, device power consumption, and operating voltage to quickly calculate the theoretical runtime on a full charge
• Supports mAh/Wh and mA/W unit combinations

1. Open the tool page — no installation needed
2. Enter the battery capacity and pick a unit (mAh or Wh), then enter the device power consumption and unit (mA/A/W/mW); if the capacity and consumption use different unit types, also enter the operating voltage
3. Click "Calculate" to see the estimated runtime, copy the result if needed, and use "Reset" to clear and start over

• This tool is completely free and requires no sign-up
• Everything runs locally in your browser — your data never leaves your device

Free online battery life estimator. Enter battery capacity, device power consumption, and operating voltage to quickly calculate theoretical runtime on a full charge. Supports mAh/Wh and mA/W unit combinations.

Open the tool page — no installation needed Enter the battery capacity and pick a unit (mAh or Wh), then enter the device power consumption and unit (mA/A/W/mW); if the capacity and consumption use different unit types, also enter the operating voltage Click "Calculate" to see the estimated runtime, copy the result if needed, and use "Reset" to clear and start over

This tool is completely free and requires no sign-up Everything runs locally in your browser — your data never leaves your device

Yes, Battery Life Estimator is completely free. No download or installation required — it runs right in your browser.