Battery Runtime Calculator
Ideal capacity ÷ current estimate with a real-world caveat.
Capacity unit
Current unit
Runtime
20 h
hours = capacity_Ah / current_A
Hours : minutes
20h 0m
≈ 1200 minutes total
Real-world runtime is typically shorter due to Peukert effect, cutoff voltage, temperature, and converter inefficiency.
What is this tool?
A first-order runtime estimate is capacity divided by load current (with consistent units). Real batteries deliver less due to Peukert effects, cutoff voltage, temperature, and converter efficiency — use this as a ceiling, not a guarantee.
How to use it
- Enter capacity (mAh or Ah) and load current.
- Read estimated hours (and hours:minutes).
- Derate for real discharge curves and inefficiencies.
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