PCB Design

PCB Trace Width Guide for Current Carrying Tracks

Understand PCB trace width, copper thickness, current, temperature rise and practical board design limits.

Why trace width matters

PCB traces have resistance. When current flows through copper, heat is generated.

Main parameters

The required width depends on current, copper thickness, ambient temperature, allowed temperature rise and board stackup.

Copper thickness

Standard copper thickness is often specified in ounces. 1 oz copper is approximately 35 µm thick.

Voltage drop

For high-current designs, voltage drop can matter as much as temperature.

Practical design notes

Use conservative margins for power electronics, battery systems, motor drivers and LED power boards.

Use the calculator

Try the related tool and calculate your own values instantly.

Open PCB Trace Width Calculator