Battery Life Estimator

Estimate runtime for an Arduino, ESP32, or sensor project — including sleep-mode duty cycling calculations.

Battery capacity

Usable capacity 85%

Active current draw

Sleep / standby current

Time spent active 100%

Real-world runtime is usually lower than datasheet mathematical values due to voltage sag, temperature fluctuations, and aging. The 85% usable-capacity default builds in a realistic safety margin. Drop it down toward 60% to 70% for standard alkaline cells or cold deployment environments.

Estimated Runtime

—

Average current draw: —

1h1d1wk1mo1yr

Visual indicator matches estimated runtime on a logarithmic scale.

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