The needs of the child, the income of the parents, the standard of living the child is accustomed to and the state's formula for child support are some of the factors that are used to determine child support, notes FindLaw. The custody arrangement for the child is also considered.
A parent who has sole custody of a child will typically be paid child support by the non-custodial parent, states FindLaw. When the parents have joint custody of the child, the court considers the amount of time the child spends with each parent to determine if child support is warranted in that case.
If a parent's financial circumstances change or the needs of the child change, either parent can request a child support modification from the court. Generally, the change has to be significant to qualify for a modification hearing, according to FindLaw.