PCB Trace Resistance Calculator

Find the resistance of a copper PCB trace.

Trace length

Trace width

Copper weight

Resistance (mOhm) 96

Formula: R = rho * L / (w * t)

Step-by-step with your numbers:

1. Values used:

2. Trace length = 100

3. Trace width = 0.5

4. Copper weight = 1

6. Resistance = 96mOhm

Did we solve your problem today?

A PCB trace has resistance set by its length, width and copper thickness.

The math behind it

R = resistivity x length / (width x thickness). 1 oz copper is about 0.035 mm thick.

100 mm of 0.5 mm wide, 1 oz trace is about 96 mOhm.

How do I lower it?

Make the trace wider, thicker (more copper) or shorter.