Are hard boiled eggs heavier than raw eggs?

Unless the egg is cracked, nothing is lost from boiling an egg, so the weight of a hard boiled egg should be the same as a raw egg. The hard boiled egg is slightly less dense, though.

While it may be true that boiling an egg denatures the protein inside, making it more of a solid, no matter is lost from the process as the eggshell is virtually impermeable and nothing gets into the water, as long as there are no cracks. It is possible for an egg to crack with too much heat from boiling, but even if this was to happen, the egg would largely stay together because it is a solid once boiled.