What are the XP levels for units in Civ 5?

Question

Is there a table or formula to specify what the XP "steps" are for units in Civilization 5?

For example, if a unit will receive +30 XP from military buildings, how can I tell what level it will be?

Answer 1

The promotion costs for the next level can can be calculated by Previous level XP + (10 * Next level)

• So for level 1 : 0 + (10 * 1) = 10
• Level 2 : 10 + (10 * 2) = 30
• Level 3 : 30 + (10 * 3) = 60
• Level 4 : 60 + (10 * 4) = 100

And so on.

Source : Civ fanatics forum