I wash mine in warm, charlie's, and sometimes with white vinegar for the rinse, and then hang them to dry. Hasn't seems to cause them any problems...

Why do you hang them to dry? Does the dryer damage them in some way?

I wash mine separately and have always dried them.

I've been putting mine in the dryer, too. They seem fine.

I use a LOT of microfiber cloths and I wash them like plumbly22 - Charlie's Soap and hang to dry. I'd avoid using Tide on them because Tide has been shown to build-up on cotton fabrics, so it will do so even more on microfiber cloths. I hang EVERYTHING to dry - because dryers shorten the life of fabrics and elastic and is a total waste of electricity. If you dry microfiber cloths/towels in the dryer, it's suggested you don't use high heat (use low or medium heat) and pull them out before the load is completely done because they dry much faster than other things in a mixed load.

-Grainlady