Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Forward voltage

Required number input.

Current

Required number input.

Compute the power dissipated by an LED from its forward voltage and current. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Power dissipation

The resulting power dissipation returned as a number.

• LED forward voltage, current, power, efficacy, intensity, wavelength, and viewing angle depend on junction temperature, binning, drive waveform, optics, aging, and the manufacturer's measurement convention. Thermal design and absolute maximum ratings remain separate.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

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  Compute the current through an LED in milliamps given the supply voltage, forward voltage, and series resistor.

• LED Forward Voltage Vs Current

  Shockley-diode forward voltage estimate from current, saturation current, ideality factor and junction temperature; series resistance omitted.