Choosing the best one that matches your needs can get difficult. You'll find tons of applications out there offering disk cleanup for Mac. So, here are our top picks of the best Mac cleaner software in 2021. Thanks to Mac cleaning and optimization software, you can give your Mac's storage a clean sweep and free up space within seconds. Manually locating and removing these unwanted disk-consuming files can be exhausting and futile. They also have varying sizes (some are tiny files while some may run into gigabytes) and are scattered across several folders on your Mac. That could be because there are excessive junk files occupying your Mac's storage disk. Or is it displaying a 'Your disk is almost full' error message? Does your Mac feel a little slow and unresponsive?