Hi, Quoting the docs for boost::numeric_cast: "There are several situations where conversions are unsafe: [...] Conversions from floating point types to integral types." What about conversions from integral types to floating point types? E.g. from 64bit int to double. The following example shows what I mean: #include <iostream> #include <cmath> #include <boost/numeric/conversion/cast.hpp> int main() { const uint64_t i = 123445678911188878; std::cout << "i=" << i << std::endl; const double d = i; std::cout << "d=" << std::fixed << d << std::endl; std::cout << "next=" << std::fixed << std::nextafter(d, std::numeric_limits<double>::max() ) << std::endl; std::cout << "prev=" << std::fixed << std::nextafter(d, -std::numeric_limits<double>::max()) << std::endl; // I'd expect the following cast to fail const double dd = boost::numeric_cast<double>(i); std::cout <<"dd=" << std::fixed << dd << std::endl; return 0; } prints i=123445678911188878 d=123445678911188880.000000 next=123445678911188896.000000 prev=123445678911188864.000000 dd=123445678911188880.000000 because that integer cannot be represented in double precision Is there something in Boost to help here? Thanks in advance