Battery runtime calculator
Estimate approximate battery runtime from Ah capacity, voltage, and load by power (W) or current (A). Results are indicative only.
Result is approximate — real runtime depends on battery type and conditions.
Input mode
Capacity (Ah)
Voltage (V)
Power draw (W)
Result
Runtime: 20 h
Total: 0 min
How to use
1. Enter battery capacity (Ah) and voltage.
2. Choose power or current input mode.
3. Enter load draw.
4. Read estimated runtime — approximate only.
Example
Battery runtime calculator
Estimate approximate battery runtime from Ah capacity, voltage, and load by power (W) or current (A). Results are indicative only.
When to use
• When you need a quick estimate without spreadsheets.
• When you want privacy — calculations stay on your device.
Limitations
• When you need certified engineering or legal calculations.
• When site-specific conditions require a professional survey.
About this calculator
Estimate approximate battery runtime from Ah capacity, voltage, and load by power (W) or current (A). Results are indicative only.
Preguntas frecuentes
Is my data uploaded?
No. All math runs locally in your browser.
Is this tool free?
Yes. No account or subscription required.