A bottle brush is designed to fit into spaces a standard sponge can’t. This cleaning tool—basically a wand with a brush head on one end—fits easily into tall, slim, and narrow-mouth bottles, such as water bottles, coffee carafes, and baby bottles. Curious to see how well they worked, we gathered five popular, widely available models, priced from $4.99 to $13.94, and got to testing.
First, we wanted to see if each brush could fit into a variety of bottles, including our winning glass and plastic water bottles, a narrow-mouth glass bottle, a baby bottle, a glass carafe, and a stainless‑steel coffee carafe. (The answer: Yes, though none of the brushes fit into an exceptionally narrow-mouthed glass water bottle with a roughly ¾-inch opening.) Then we used each brush to remove sticky honey from inside each container and to scrub smoothie remnants from water bottles. We washed each brush multiple times, checking for wear and tear, odor retention, and leftover food particles throughout testing. We also had volunteers use the brushes at home for a week.