I do not own a dishwasher. And to keep things clean, I usually change my sponge out every week - more often if someone left water in it and it gets that sunky smell. Because these are not as thick as the pink Scotch sponges I was purchasing from my local market or department store - I'm not wasting halfway decent sponges. Along with the not wasting, I got these 12 sponges for $11. Similar scrubby sponges purchased locally would cost me $3.59 for 2. As an added bonus, these are cheap enough that I get pink foam from them. I kinda like that!