In golang, both uint64 and float64 are 8 bytes in size. I expected that the maximum number represented in uint64 (which would be 1<<64 - 1, all bits set to 1) would be greater or at least equal to the maxium number represented for float64 which, being made up with sign, exponent and mantissa, I expected it to be lesser.

Link to playground: https://go.dev/play/p/ZbVYKmTV3CW

CodePudding user response：

The reason is simple: the exponent in float64 can be 64 or higher, up to 1023.