Heat is the biggest sign you should replace an extension cord.

If your extension cord feels warm to the touch after normal use, that’s the single most telling sign it needs to go. Internal resistance is building up, and that heat can lead to melting, arcing, or a fire.

Beyond warmth, look for stiffness or brittleness in the insulation. A cord that’s been coiled tightly for years or left in the sun will get hard and crackle when you bend it. That means the jacket is failing, even if you can’t see a split.

Also check the plug prongs. If they’re discolored, pitted, or loose in the outlet, the connection is compromised. And if the cord is more than a decade old, just replace it. The rubber degrades slowly, but surely.

Don’t wait for sparks or a burning smell. By then, it’s almost too late.