A character who reaches a specified experience point total advances in capability.
Take the average (the number in parenthesis) and gain that many hit points. Whatever amount you ended up with (from the roll or the average) you add your constitution modifier and add your sweet new hit points to your characters total! A note on dm house rules.
experience and character advancement in 5e if you look at the table for level advancement by experience points, in the dnd 5e players handbook (phb) p15, you can see that not only do you need more experience points for each level, but that the additional number needed to progress from one level to the next increases as your level gets higher.
For advancement beyond 1st level, refer to the class feature pages.
The character advancement table summarizes the xp you need to advance in levels from level 1 through level 20, and the proficiency bonus for a character of that level. Consult the information in your characters class description to see what other improvements you gain at each level.
a character who reaches a specified experience point total advances in capability.
while there are a few things that can be done to min-max your character in 5e, regular characters dont lag very far behind, making min-maxing less efficient than pathfinder. This means that character creation and leveling dont have to take nearly as long to do, but players who like system mastery benefits sometimes find it lacking.