PCB Trace Width Calculator

The pcb trace width calculator takes ambient temperature, the trace is…, length, max current, max. desired temperature rise, trace thickness (t) and one way and returns trace temperature, power dissipation and cross section cm. It is built for quick answers, for checking somebody else’s arithmetic, and for the moments when a formula book is not within reach.

What Is the PCB Trace Width Calculator?

The pcb trace width calculator turns ambient temperature, the trace is..., length, max current, max. desired temperature rise, trace thickness (t) and one way into trace temperature, power dissipation and cross section cm.

It is a quick way to get from the numbers you have to the number you need, without setting up a spreadsheet or reaching for a formula.

How the PCB Trace Width Works

Each result follows from the ones before it, and the calculator shows every step, so a surprising answer can be traced back to the input that caused it.

Round your inputs to the precision you actually know, and keep more precision than that in the intermediate steps.

Getting a Result You Can Trust

Run the calculation twice with slightly different inputs. A sensible calculator moves its output in proportion; a wild change points to a unit or a decimal point problem in what you entered.

Write the inputs down next to the answer. It takes a moment and it is the difference between a number you can explain and one you cannot.

A Worked Example

Working through an example, with ambient temperature set to 10, the trace is... set to 0.024, length set to 5, the calculator returns cross section of 27.26541, and trace temperature of 110, and trace width (w) of 1.97862. Substitute your own figures and the same steps produce the same kind of answer.

Frequently Asked Questions

What do I need to work out trace temperature?

Enter ambient temperature, the trace is..., length, max current, max. desired temperature rise, trace thickness (t) and one way. The calculator then works through the relationship and reports trace temperature, power dissipation and cross section cm.

What does the pcb trace width actually calculate?

It takes ambient temperature, the trace is..., length, max current, max. desired temperature rise, trace thickness (t) and one way and converts them into trace temperature, power dissipation and cross section cm using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.

How should I enter ambient temperature?

Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.

Do I have to fill in every field?

Only the fields a particular result depends on. If you leave one blank, the results that need it simply show a note instead of a number, and everything else still works.

Does anything you type get stored?

No. The whole calculation runs inside your browser, and nothing you enter is uploaded, logged or sent anywhere.

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