The rule of thumb I use is this: get an external drive at least three times as large as the amount of data you expect to back up.įor example, my primary Windows machine has a roughly 922GB (gigabyte) drive, of which around 478GB are used. Of course, more capacity also means a more expensive drive. It’s pretty easy to say you can never have too much capacity. Opinions and quality change often, so make sure to pay attention to the dates of specific recommendations you find. SSDs are not worth the expense to be used as external drives, though they otherwise could be. Make sure the interface is USB3 or better. Begin by selecting an external drive that is sufficiently large to hold your backup images - I recommend three times your disk space used, at a minimum, though larger is always better.
