What length of 12-gauge extension cord is safe for a 15-amp miter saw?

100 feet is fine for a 12-gauge cord on a 15-amp miter saw. Breaker tripping isn’t the issue—it’s voltage drop. A 12-gauge cord can handle 15 amps at 100 feet without enough voltage loss to hurt your saw or trip anything. For almost every job site, 50–100 feet of 12-gauge works perfectly.