Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Current Amperes (A)

Required number input.

Resistance Ohms (Ω)

Required number input.

Resistive heat dissipation I²R in a conductor or load at specified RMS 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]

Loss Watts (W)

The resulting loss watts returned as a number.

• Electrical estimates require the correct AC or DC model, RMS and phase conventions, source impedance, grounding, conductor conditions, protection, temperature, harmonics, faults, and applicable standards. Nominal ratings are not automatically compatible design limits.
• 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 assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Cable Sizing Current Capacity

  Usable conductor current rating from a supplied base ampacity times installation and temperature derating factors; not a code sizing determination.

• Fiber Attenuation

  Optical fiber power loss in decibels from attenuation per kilometer times fiber length; excludes connectors and splices.

• Power Factor Correction Capacitor

  Ideal single-phase shunt capacitance needed to raise lagging power factor at fixed real power, RMS voltage and frequency.