A note, IPC-2221 is quite old, and known to be off by a good bit. This one uses IPC-2152:
https://www.smps.us/pcb-calculator.htmlMore discussion here:
https://www.ourpcb.com/trace-width-calculator.htmlNote that trace width doesn't mean much over short distances, where component pins act as heatsinks keeping the trace cool, or where current is still spreading out from the pins themselves (a trace width of say 200 mils is not even meaningful for a length of 100 mils), or for pours/polygons that have arbitrary shapes.
For polygons in particular, the area of the shape matters as much as the width of the current path through it. Even if current doesn't spread out over the whole area, heat does. It helps to have wide pours, even if the added area isn't carrying any current as such!
You can also get 2 and 3 (and even 4) ounce copper for not much added cost these days. You can also use identical traces/pours routed on both copper layers (assuming no trace crossings are needed), in which case merely 1 or 2 ounce will do.
Tim