It's the quietest electric grinder I've used but I didn't want to diss any competitors in particular! It has a nice low rumble for probably 45 seconds grinding a single dose. I think the noise level is helped by the fact that the motor is completely enclosed by the heavy stainless steel burr, which basically eliminates its noise, and the fact that it spins slower than other grinders because it has a larger grinding area.

It is easy to say the espresso machine is the quietest because basically everything else uses the same pump, which is way louder and more annoying than ours, but grinders are much more variable not just in terms of noise level but also how annoying the noise is.