Pokemon hatch at the same level as your trainer when you first acquire them, up to trainer level 20.
- Obtaining an egg when your trainer is level 10, the egg will hatch into a level 10 Pokemon even if you leveled up.
- Due to the level cap, even if you found the egg at trainer level 30, the egg will hatch into a level 20 Pokemon.
The following charts below help you easily determine what IV's your hatched Pokemon have, assuming you are at least level 20.
Pokemon GO Eggs List