Don't connect two extension cords together.

Don’t do it. Daisy-chaining extension cords is a fire risk and a tripping hazard. The connection point is weak, voltage drops, and cords overheat more easily.

The math is simple: every connection adds resistance, and resistance generates heat. Two cords also means two points where plugs can get pulled apart, exposing live prongs. Even if you tape them together, the risk is real.

If you absolutely have to, use the same gauge (12 or 14 AWG for heavy loads), keep the combined length under 50 feet, and never run more than a light load. But honestly, just buy a longer cord. They cost $20–30 and last years.

Buy the right length cord instead. Future you will thank you.