Facts are things that are true. Opinions are things we believe. Some of our beliefs are true. Others are not. Some of our beliefs are backed by evidence. Others are not. Value claims are like any other claims: either true or false, evidenced or not. The hard work lies not in recognizing that at least some moral claims are true but in carefully thinking through our evidence for which of the many competing moral claims is correct.
Justin P. McBrayer, Why Our Children Don’t Think There Are Moral Facts