How many emails do professors get every day? When I was in academic publishing, I received about 50? emails a day. The bulk of these (~60-70%) would be semi-automated emails of the form "so-and-so has agreed to review this paper" or "the first proofs of so-and-so paper are now available at this internal link". There'd be a few (&lt;5) internal emails about e.g. meetings, new hires/resignations, policies, and so on. There's the occasional promotional email sent by other publishers or conference organizers (I have no idea why they would email me, but not mine to reason why), and finally there are actionable emails: author corrections, complaints, questions, initiatives, replies from acquisition attempts, and so on (usually more than 1, but less than 10, of these every day).

What does it look like for professors? I've had one professor tell me that his inbox resembles a black hole, and I'm curious how black is black in this case.
i get well over a hundred emails per day despite fairly intense efforts to unsubscribe from lists and block spam.  Some are from students, some are from faculty colleagues, some are from research colleagues at other institutions, some are marketing junk, and lots are from administrators at my own institution.