“Six million” is not, and was never intended to be, a precise accounting. But the number, which has now been part of the public consciousness for more than 50 years, would never have continued to be cited if it did not mirror the scholarly tallies that have followed in the succeeding decades, and confirmed that rough figure.
Quoted from https://themuslimtimes.info/2019/05/02/holocaust-facts-where-does-the-figure-of-6-million-victims-come-from/
I thought quoting a Muslim page would put this into its proper perspective.