For $75.00, I will compute child support payable under Virginia Support Guidelines for you, but you can get it done for free by contacting the Court Service Unit of the appropriate Juvenile and Domestic Relations District Court.
They (and I) will request recent paystubs from each of you as well as the amount one of you may be paying for insurance for the children through your employer. This amount is the difference you would be paying if you were single and the amount you are paying for the family coverage at work. The cost of monthly day care and any recurring medical expense (I hope there are none!) also are plugged into the formula set by the General Assembly in §20-108.2 of the Code of Virginia. Once the calculation is made, if desired, appropriate orders for support (and custody and visitation for that matter) are entered by the court or I will put the figures into the separation agreement if you are getting one.