Q. If I have $2300 federal tax calculated; will that come out of the 4000 in child tax credit I have?
A. Simple answer: Yes.
On form 1040, your taxable income is first calculated. Then the tax is calculated on that. Then tax is reduced by any tax credits, including the child tax credit. Tax "Due" comes after applying any credits and payment (e.g. withholding).
If you had $2300 calculated tax, $2300 (of your maximum $4000) Child tax credit would reduce that tax to zero and you would have no tax due. You may or may not get the remaining $1700 child tax credit, as a refund, depending on how much earned income you have.
