The LED bulb shelf at a shop can be overwhelming: the same wattage, different color temperatures, a different base, a beam angle printed in tiny letters. You buy on a guess, and at home the light turns out too cold, too narrow, or the bulb simply doesn’t fit the socket. In this guide we break down choosing an LED bulb into six parameters that actually matter – and show you how to read them on the packaging before you even open the box.