3.3% is the number — and it's borderline.

You’ll drop about 2 volts, or 3.3% of 120V, over that 50-foot 14-gauge cord at a full 15-amp load.

That’s within the 3% drop many codes recommend for a single branch circuit, but right at the edge. For a power tool that’s already finicky about voltage, you might notice it stalling under load. For lights, they’ll dim slightly but probably won’t complain.

The real issue: that cord is 14 gauge, which is rated for 15 amps, but 50 feet is long enough that resistance adds up. If you can bump up to 12 gauge, you’ll drop to about 2% — safer, cooler, and your tools will thank you.

Don’t push it past 15 amps on a 14-gauge cord this long.