If the child tax credit reduces your federal tax liability to zero you may receive a tax refund called the Additional Child Tax Credit.
You can calculate your child tax credit amount by using the free tax calculator provided by TurboTax.
You can see the child tax credit worksheet on IRS Publication 972 which begins on page four.
There are two different methods to calculate the leftover money.
If you have one or two children;
The refundable tax credit is the lesser of the two amounts;
1) the leftover money of the child tax credit or;
2) 15% of the taxpayer’s earned income over $3,000
If you have three or more children;
1) the leftover money of the child tax credit
2) Which ever amount is the largest between these two; 15% of a person’s earned income over $3,000 or;
The total of Social Security and Medicare taxes paid minus the the money gained from the Earned Income Tax Credit.