LED Resistor API
LED current-limiting-resistor maths as an API, computed locally and deterministically. The resistor endpoint sizes the series resistor for a single LED, R = (V_supply − V_forward) / I, and returns the resistor power dissipation (I²·R), the LED power, a recommended resistor wattage rating and the nearest E12 standard value (rounded up so the LED current stays at or below the target). The series endpoint sizes the one shared resistor for several LEDs wired in series, where the forward voltages add, R = (V_supply − n·V_f) / I, and flags when the supply is too low for the string. The parallel endpoint gives the per-LED resistor for LEDs in parallel (each needs its own) and the total current the supply must deliver. Currents are entered in milliamps. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, maker, Arduino and hardware app developers, LED and lighting-circuit design tools, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is LED resistor sizing; for general Ohm's law and reactance use an Ohm's-law API and for AWG wire properties use a wire-gauge API.
api.oanor.com/ledresistor-api
