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.

Trace length (mm)

Required number input.

Trace width (mm)

Required number input.

Copper thickness (um)

Required number input.

Compute PCB trace resistance in milliohms from copper resistivity 1.7e-8 ohm m and trace dimensions. 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]

Trace resistance (mOhm)

The resulting trace resistance returned as a number.

• PCB trace calculations depend on finished copper thickness, geometry, dielectric stack-up, temperature rise criterion, ambient, neighboring conductors, return path, frequency, surface finish, and fabrication tolerance. IPC equations are approximations, not a substitute for the board fabricator's stack-up or field solving.
• 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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