Tennis Balls in the Dryer? Why the Old Hack Needs an Upgrade
July 17, 2026
Yes, tennis balls in the dryer really do work: they break up clumped down in pillows, comforters, and puffy jackets, and they can shorten drying time by 15 to 25 percent. But the old hack comes with real downsides. Tennis balls are loud enough to sound like a rockslide, and the rubber and adhesives inside them can off-gas a chemical smell when heated above about 140 degrees, right onto the bedding you sleep in. The upgrade is simple: wool dryer balls do the same fluffing job, quietly, with nothing but wool. Here is the full story.
The hack works. The ball is the problem.
Bouncing balls in the dryer genuinely fluff pillows and comforters. Just swap the tennis balls for wool dryer balls: same physics, no noise, no heated rubber smell on your bedding.
Why do people put tennis balls in the dryer?
The trick has been passed down for decades because the physics is sound. Down and fiber-filled items clump when wet, and a wet clump dries slowly and dries lumpy. A ball bouncing around the drum does two jobs at once: it pounds the clumps apart so the filling redistributes and regains its loft, and it wedges air gaps into the load so hot air can circulate instead of steaming one soggy mass. That is why a couple of balls can shorten drying time by 15 to 25 percent on bulky items.
So the hack itself deserves its reputation. The question is whether a fuzzy rubber ball designed for a tennis court is the right thing to tumble against your bedding at high heat.
Where tennis balls fall short
Tennis balls vs wool dryer balls
Wool dryer balls keep everything that makes the hack work and fix everything that makes it annoying.
| Factor | Tennis balls | Wool dryer balls |
|---|---|---|
| Fluffs pillows and down | Yes | Yes |
| Faster drying | 15 to 25 percent | 14 to 25 percent |
| Noise | Loud rubber thuds | Soft, quiet tumbling |
| Chemical off-gassing | Possible above 140 degrees | None, it is just wool |
| Made from | Rubber, glue, synthetic felt | 100% organic New Zealand wool |
| Softens and cuts static | Not really | Yes, naturally |
| Lifespan | Breaks down with heat | About 1,000 loads |
Bigger than a tennis ball and made of nothing but 100 percent organic New Zealand wool. All the fluffing power, none of the racket or the rubber smell.
How to fluff pillows and comforters with wool dryer balls
The routine is the same one your grandmother used, with a better ball. Size matters here too: a 4 inch wool ball has the heft to punch clumps apart in a heavy wet comforter, where smaller balls just get swallowed by the folds.
Bigger balls, better bounce
A tennis ball is 2.7 inches of rubber. Our wool balls are a full 4 inches of dense New Zealand wool, so every bounce hits harder, moves more air, and fluffs faster. If a little ball can do the job, a big one does it better.
Once you have the balls, they are not just for bulky loads. Use them on every cycle to soften laundry and cut drying time, and see our guide on how to use wool dryer balls for the full routine, or the head-to-head on wool dryer balls vs dryer sheets.
Two oversized balls of pure organic New Zealand wool. Fluffs down, softens laundry, kills static, and lasts about 1,000 loads.
Frequently asked questions
Do tennis balls in the dryer actually work?
Yes. They break up clumped filling and create air gaps, which restores loft and can shorten drying time by 15 to 25 percent. The catch is the noise and the possibility of heated rubber off-gassing onto your laundry.
Are tennis balls safe in the dryer?
Generally, but with caveats. Above about 140 degrees the rubber and adhesives can release a faint chemical odor, new balls can transfer dye and fuzz, and they are very loud. Wool dryer balls do the same job without those issues.
What can I use instead of tennis balls in the dryer?
Wool dryer balls are the best like-for-like swap: same fluffing action, quieter, chemical-free, and reusable for about 1,000 loads. In a pinch, tightly rolled towels also work for a single load.
How do you fluff a pillow in the dryer without tennis balls?
Dry it on low heat with two wool dryer balls, pausing once or twice to shake the pillow and break up clumps by hand. Keep drying until the inside is fully dry.
Can you dry a down comforter with wool dryer balls?
Yes, they are ideal for it. Use low heat and two to four balls depending on comforter size, and expect it to take a couple of hours. The balls keep the down moving so it dries lofted and even.
Will tennis balls damage my dryer?
They will not usually damage the machine, but they are hard on your ears and can scuff or mark the drum over time. Wool balls are soft enough to bounce for years without a scratch.
Grandma was right. Upgrade the ball.
The bouncing-ball trick works, so do it with two big wool balls instead: quiet, chemical-free, and better at it.
Get bigger balls on Amazon →4-inch XXL · 100% organic New Zealand wool · about 1,000 loads