The Ultimate Guide to Picking The Right PCB Trace Width

We know it’s imperative that you pick the right trace width for your next PCB design. You need to correct trace width so that you can route your PCB. The following rules need to be applied to your printed circuit board. Please note, there are a few exceptions for these rules and these include high-power applications and high-frequency signaling. 

The rules/characteristics you need to follow are:

  • The spacing between the traces
  • The capacity of the trace and how much current is going to flow through it 
  • The pitch and the size of the pads that will be connected to the trace 

The Trace Ampere Capacity

When it comes to trace on a printed circuit board you should be aware that there is a maximum current that can be handled. If the current is exceeded it will fail. This is because heat will dissipate and the trace will be burned or broken. 

All traces have resistance and it’s vital that this is considered when you are choosing the widths. The good news is there are a lot of trace width calculators online and they can help you achieve the correct current.

Trace Spacing

The cost of your new printed circuit board will be connected to its size. This is why it’s essential you keep the PCB as small as possible. However, if your PCB is too small there will be a limited amount of space for your route tracers. It is usually advised that you have traces that are as small as possible if you are using low power traces. This is so you have plenty of room for routing. 

If your traces are large they might take up too much space while they also offer less than perfect returns.

Trace Termination


The width of a trace can be informed by the point where the trace meets the pad. In many cases, the width of the trace is the same width as the pad. This can help with routing the traces away from a component that they connect to. In addition to this, it will also ensure space between the adjacent traces is not used up.