The English Reformation was "a series of events in 16th-century England by which the Church of England broke away from the authority of the Pope and the Roman Catholic Church". It involved the killings of many religious individuals (mostly Catholic, but also Protestants, during Mary I's reign), by official order of the state/crown (some other might have died from related sectarian violence, but that is surely hard to quantify so we can omit these). All denominations other than Anglican were forbidden.
A parallel reformation and persecution process (although with it's own idiosyncrasies) happened in the Kingdom of Scotland.
It wasn't until the English Toleration Act 1689, when freedom of worship was granted to "nonconformists who had pledged to the oaths of Allegiance and Supremacy and rejected transubstantiation" (i.e. to non-Catholics). Finally, it was in 1791 that freedom of worship was allowed for Catholics across Great Britain.
The question is "simple". How many people died in Great Britain (England + Scotland) and Ireland from state-directed religious persecution during all the above period (starting around 1532-1534)? Ideally, it would be great to have an idea of numbers by denomination.
PS: here, for instance, there is a list of people considered "martyrs" by the Catholic Church as part of the English Reformation. Yet, not all killed were considered martyrs. So the list is incomplete.