TOOLSElectronics calculators.

Free calculators for hardware builders. Each one is worked from a real OTD board, with the formula and a cited source.

CalculatorLiPo battery runtime calculator (ESP32 / microcontroller)Estimate runtime from battery capacity, average current draw, and usable capacity. Worked from a real ESP32-S3 board's measured budget.
CalculatorWS2812 / NeoPixel power supply calculatorSize a 5 V supply for an addressable LED string from pixel count, per-pixel draw, and headroom. Grounded in the WS2812B datasheet figure.