Following on from my two IPC 22211 posts, IPC 2221 standard trace widths and the one where I normalised them for KiCad Traces Net classes, I have built an online calculator that you can use to work out the required track width with different parameters.
IPC-2221 PCB Trace Width Calculator
External Layer (Outer)
Internal Layer (Inner)
Calculations are approximations based on empirical data from the IPC-2221 standard guidelines.
This IPC 2221 standard guidelines calculator for PCB trace current and heating is indicative; thermal rise of trace width should be checked empirically or by full calculations.
I mostly aim to produce 2-layer PCBs with 1 Oz copper, and base most of my sizing on only a 10 °C allowable tempriture rise. As such, most of my track widths are quite conservative and allow for derating without risking damage. My nominal widths can be found on my KiCad Traces Net classes post, which also has the minimum recommended PCBway trace width as an option. My values are in millimetres, and are rounded up; I use a 0.2540 mm grid (0.01 inch / 10 thou).
The above calculator also shows you the track width for internal traces as well (4 or more layer PCBs).
- IPC stands for “Institute of Printed Circuits”; more details are available on its Wikipedia page.