Varies hugely.
DD's school don't have a homework timetable, with the idea that teachers don't set homework for the sake of it. They usually give a week to do it, so fitting it in is not an issue. Theoretically I think it's supposed to be 45-90 minutes a night in KS3.
However, in practice, very little is set. In year 7 and 8 it varied from 13 seconds (we timed!) to a couple of hours per WEEK. Admittedly, that is for an able student who will have had less to do if it was "finishing off". There seemed to be more art than anything else - which at least got the message across that art GCSE is time-consuming!
Now in year 11, and there's still only a few hours a week of "hand-in" work, although obviously revision is now ongoing. There are revision sessions most days after school.
On the one hand, it's been very difficult to establish any good homework habits, because it's been entirely possible to do it all on Sunday evening. That has a knock-on to good revision habits, too.
On the other hand, they seem to be doing pretty well without it! In DD's case, there's one subject where I think more written work might have made a difference.
I loved a comment I saw once from someone who said that their kids and the neighbours' had come out of primary school with the same results. The neighbours' kids went to private school, their kids went to the local comp. They emerged from secondary with very similar grades, but the neighbours' kids had done a lot more homework.