Support is paid in the form of monthly instalment by the parent who doses not have custody to the one who does.
In case of shared custody, the Judge will only rarely grant support if there is a very substantial difference of income between parents.
There is no fixed scale established by statute.
Each judge will estimate the amount of monthly support necessary depending on the income and expenses of the parents, the age and needs of the child, the number of children.
For instance with an income of 2000 €/ Month a parent could expect to pay for one child between 150 and 300 € Month.
At any time until the child is capable of supporting itself, a parent can ask a judge to increase of reduce the amount of support depending on the changes in the situation of parents and child.
Obligation to pay child support does not stop when the child is 18. This obligation continues until the child is capable of subsisting alone (usually when studies are over).