Child Support Calculator for USA

This Child Support Calculator is the most comprehensive available online. It is based on the Income Shares Model (used by 40 states in the United States) and the Percentage Income Share Model used by 6 states. This calculators puts into consideration the minimum $600 expected for annual Child support.

Children are such priceless and adorable gifts, but taking care of them can be a huge responsibility. You know the popularly saying: every child needs support. Well, so does the adult taking care of the child.

We created this child support calculator to help you with details about child support payment. Before we go on, let us look at the meaning of child support.

What is child support? 

According to the Legal Information InstituteChild support refers to the sum that the noncustodial parent must pay to the custodian. This sum serves as a parental contribution for the child’s basic living expenses, such as food, clothing, shelter, health care, and education.

Child support is the money that a parent that is not in the custody of the child is supposed to pay. This money is to support the child’s basic needs.

Calculating the amount you are going to pay for child support in the USA can be confusing because of the different child support models. You do not need to be confused because we will be looking at states in the US and the child support models they use.

The Different States in the USA and the systems of Child Support they adopt (with graphics)

The child support model that you would use is largely dependent on your location because different states in the US adopt different child support models.

Below is a list of the states in the US and the child support models they adopt. Scroll carefully to see the child support model that is best for you.

Massachusetts Income Shares
Michigan Income Shares
Minnesota Income Shares
Missouri Income Shares
Nebraska Income Shares
New Hampshire Income Shares
New Jersey Income Shares
New Mexico Income Shares
New York Income Shares
North Carolina Income Shares
Ohio Income Shares
Oklahoma Income Shares
Oregon Income Shares
Pennsylvania Income Shares
Rhode Island Income Shares
South Carolina Income Shares
South Dakota Income Shares
Tennessee Income Shares
Utah Income Shares
Vermont Income Shares
Virginia Income Shares
Washington Income Shares
West Virginia Income Shares
Wyoming Income Shares
Delaware Melson Formula
Hawaii Melson Formula
Montana Melson Formula
Alaska Percentage of Income
Mississippi Percentage of Income
Nevada Percentage of Income
North Dakota Percentage of Income
Texas Percentage of Income
Wisconsin Percentage of Income

From the table above, you will notice that there are three child support models used by states in the USA. According to the National Conference of States Legislatures, child support guidelines in each state follow one of three models: the income share model, the percentage of income model, and the Melson Formula.

Yes, there are three models for calculating child support but we are focusing on just two models: the income share model and the percentage of income model. We are focusing on these two models because they are commonly used. Over 90% of states in the USA use either of the two models.

Alright, since you have seen the different models used by different states in the USA, it is good you understand what they mean and how the models work.

The Income Shares Model

The income shares model works on the premise that the child/children should receive the same financial support from their parents just as they would if their parents were together.

This model takes the income of both parents and then adds them together before deriving the percentage amount that both parents will pay. Here, the specific amount is determined by looking at the net income of the parents and the number of children under the support order.

We will be defining some common income shares models terms to make the definition clearer. It is good you understand the following terms to grasp the concept of the income shares model:

Custodial Parent

A custodial parent is also the primary parent; this parent shares a home with the child/children. This means that the court of law has given primary, legal, or physical custody to the parent.

Non-custodial parent

A non-custodial parent is a parent that does not live with the child/children for a majority of the time. The child/children may pay occasional visits. Most times, this situation usually arises after a separation or divorce, where one parent has primary physical custody instead of the parents sharing joint custody.

Number of overnights

The number of overnights refers to the number of times that the child/children go to sleep at a parent’s house and wakes the next day at the parent’s house. You calculate the number of overnights by the number of days that this happens.

The expected cost of Raising a Child

The expected cost of raising a child refers to the amount of money that the parents of the child/children would spend to raise the child from the early stages until 18 years. This differs from state to state and it is usually determined by the jurisdiction.

Net Income

Net income refers to the total income that a parent gets from all sources minus the following: federal income tax, state income tax, social security, mandatory retirement contribution, union dues, health/insurance premiums, loan repayments, etc.

Basic Child Support Obligation

The basic child support obligation refers to the support that the parent gives to the child. This support covers food, clothing, shelter, and other basic expenses.

Now that you understand the income shares model and the terms often used, let us look at the percentage income shares model.

Percentage Income Shares Model

Few states in the USA use the percentage of income model. (You can check the tables above). This model uses a certain percentage of the non-custodial parent’s income to determine the amount of ordered support. Sometimes, the percentage that the parent will pay will not change even if the income increases or reduces (the percentage is flat).

In some case, the percentage of income changes when the non-custodial parent’s income changes. Let us get familiar with some percentage income shares model terms:

Primary Physical Custody

This term addresses the situation when one parent spends more time with his/her child/children than the other. This simply means that one parent is more responsible for caring for the child/children.

Shared Physical Custody

Shared physical custody means that a child/children live with each parent for an equal amount of time. Shared legal custody means that the parent shares the legal responsibility for taking care of the child. Children involved.

Divided Physical Custody

Divided physical custody also known as spilt custody refers to the arrangement where one parent has sole custody of one or more children while the other parent has sole custody of the remaining children. Parent often spilt custody for different reasons.

Hybrid Physical Custody

In this kind of custody arrangement, at least one parent has physical custody of at least one of the children, and the parents share the custody of at least one of their children. (we refer to physical custody in this context).

Basic child support rules   

If you are thinking of a child support system to adopt, there are some rules you will need to follow. It is important you get familiar with these rules to prevent future misunderstandings. Below are a few rules that would help you:

  • In divorce and dissolution cases involving children, the child support must be paid, even if the parents might agree otherwise.
  • The child support is paid on behalf of the children, not for the benefit of the custodial parent.
  • Before the court can change the child support amount based on unusual circumstances, the court must be shown proof by clear and convincing evidence that manifest injustice would result if the support award is not changed.
  • If a parent does not take physical custody of the children for at least 30% of the year, as agreed, the other parent can file a motion with the court to modify the support order.

How to use the USA child support calculator

It is easy to calculate your monthly or annual child support with this calculator. All you need to do is to follow these simple tips:

Select your state (there are different child support models when you select your state the proper model is used to calculate your annual or monthly child support).

Once you have selected your state, you need to fill in some basic information like:

  • Number of children
  • First parent name
  • Second parent name
  • Number of overnights
  • Annual net income after tax

Once you fill in the boxes correctly, the calculator will automatically calculate your monthly/annual child support payment.


This calculator provides an estimate of how much child support you will have to pay depending on your location and other factors (factors like your income, custody arrangement, etc.).

The result you will get will only be accurate if you accurately enter your income and deduction amounts. Your attorney may decide to use another model that may give you a slightly different result.

The results from this calculator should not be taken as ‘law’ but rather as an estimate or a guide.

NoteThe judge can determine the amount of child support to be paid. 

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