You are right, but as theamk pointed out in another comment, the spec does tell you to "expect no more precision or range than" IEEE754 doubles. So, don't count

You are right, but as theamk pointed out in another comment, the spec does tell you to "expect no more precision or range than" IEEE754 doubles. So, don't count on arbitrary precision... [1] https://datatracker.ietf.org/doc/html/rfc7159#section-6 https://datatracker.ietf.org/doc/html/rfc7159#section-6