Battery Runtime Calculator
Free, instant battery runtime calculator with step-by-step solutions, transparent formulas, and verification.
Quick answer
Battery runtime is an estimate of usable energy divided by load power, adjusted for the selected efficiency or usable-capacity factor.
Formula and calculation method
Runtime (h) = Ah × V × usable fraction × efficiency / load W; in current mode, runtime = Ah / load A × efficiency.
Use the interactive Toolune page
Enter your values in the browser tool to see the result, worked steps, assumptions, and related learning guides.