A bath bomb is a palm-size ball or disc, generally made of baking soda, citric acid, oils, and dyes that dissolve in water. And it can transform a simple soak into the highlight of one’s day, calming nerves and softening skin while entertaining bathers with fantastic fizz, soothing scents, and captivating colors.After soaking in data from 55 on-the-record baths involving bath bombs from 16 different brands, we’re certain that Lush makes the most luxurious bath bombs—they provide multisensory pleasure and effectively moisturize skin.For a dye-free or added fragrance-free bathing experience, consider bath bombs from Old Whaling Co. If you’d prefer to spend less, Purelis Natural Bath Bombs, bought in bulk, provide a pleasurable bathing experience starting at around $1 each. We also think the Two Sisters Squishy Surprise Bubble Bombs gift set is a worthwhile splurge for kids.