Upvote:1
Details varied very much over time.
In a feudal system, the overlord grants lands to a vassal in exchange for loyalty and military service. This land grant should be roughly proportional to the services owed, and allow the vassal to live in the style appropriate to his or her rank.
It was the interest of the vassal to turn this "loan" of lands into a permanent, inheritable possession of the family. It was in the interest of the overlord to retain flexibility to assign lands to his or her current supporters.
Over the centuries, the titles of nobility (and some of the rights that came with it) got divorced from the lands that originally went with the title. The title could not be split during an inheritance, the lands could. Lands could become dowry while titles would not. Etc.
Upvote:4
That depended very much on many factors:
A higher ranking title didn't automatically bring more benefits. It usually did, but was not the rule. A count is a title lower than duke or archduke. Yet, some counts (the counts of Flanders and of Holland) were pretty powerful. Whereas an Austrian archduke was mostly an honorary title. There were many princes with little power and barons with immense power.
There wasn't a typical land grant for any title. That was the king's privilege. He awarded land and titles as he saw fit. The duchy of Normandy was given away or granted almost as ransom payment or blackmail. The first duke of Normandy was a Norman, he got his duchy to stop him from pillaging other parts of France and protect the kingdom. I doubt very much if the king like that, but he didn't have many alternatives.
Your question is very broad, I give some reasons why it varied so much. Even the titles changed over times. A Roman comes (count) was a higher position than a ducus (duke). Later that changed around. By the way, the titles comes and ducus were, when originally created, positions. Not inheritable titles. That changed as well (and pretty quick at that).
What you infer is a kind of system where a higher ranking noble got more land than a lower ranking noble, based on seniority. As in the civil service today. That definitely was not the case.