PCB Trace Width Calculator

Calculate the minimum trace width for your PCB design using IPC-2152 and IPC-2221 standards. Fast, accurate, and free to use.

I’ve been working on a PCB design for a 12V LED strip controller lately, and I was stuck trying to figure out the right trace width—too narrow and I worried about overheating, too wide and I’d waste board space. That’s when I came across this article, and it clarified so much, especially the part about IPC-2152 being more accurate for modern designs than the older IPC-2221. I immediately tried the PCB trace width calculator with the LED example’s specs: 5A current, 20°C temp rise, 1oz copper, and external layer—and sure enough, it gave me the 110 mils minimum width the article mentioned, which matched what I needed. What I really appreciated was the safety recommendation to add 20-50% extra width; I went with 30% more, so 143 mils, to account for manufacturing tolerances I hadn’t even thought about before. The article also reminded me to consider ambient temperature, which is key since the controller might sit in a closed enclosure. Now I feel way more confident in my design, and I’ll definitely use the calculator again for the motor driver circuit I’m planning next—this time referencing the 8A motor driver example to double-check my inputs.

PCB Trace Width Calculator