Battery Life Calculator

Calculate battery life from capacity and current draw. Supports mAh/Ah capacity and mA/A current with adjustable efficiency factor. Shows theoretical and effective runtime with energy calculations.

How to Use Battery Life Calculator

Enter battery capacity in mAh or Ah, current draw in mA or A, and efficiency percentage. Click Calculate to see theoretical and effective battery life in hours, days, and minutes, plus energy calculations.

Step-by-Step Instructions

  1. Enter battery capacity and select unit
  2. Enter current draw and select unit
  3. Set efficiency percentage
  4. Click Calculate Battery Life

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