US Child Tax Credit Calculator (2025)

How to use this calculator

The estimator turns four pieces of information into a credit figure: your filing status, the number of qualifying children under 17, the number of other dependents, and your income. Two income boxes matter, and people often confuse them. Adjusted gross income (AGI) is your total income after adjustments, and it decides whether the credit starts to phase out at the top. Earned income is your wages and net self-employment income, and it decides how much of the credit can come back as a refund if your tax bill is small. Enter both honestly, because using one in place of the other is the most common reason an estimate comes out wrong.

Once you enter those figures, the result splits into two numbers worth reading separately: the total credit you could claim, and the slice of it that could be refundable. The first reduces the tax you owe. The second can be paid to you as cash even when you owe little or no tax. Understanding why those two numbers differ is the whole point of the tool.

The four tests a qualifying child must pass

For the full $2,200 credit, a child has to meet every one of the IRS tests, not just one or two. Getting a single test wrong is enough to lose the credit for that child, so it is worth checking each:

• Age: the child must have been under 17 at the end of the tax year. A child who turned 17 during the year is over the limit for the main credit, though they may still bring the $500 Credit for Other Dependents.
• Relationship: the child must be your son, daughter, stepchild, foster child, sibling, half-sibling, step-sibling, or a descendant of any of these, such as a grandchild, niece, or nephew.
• Residency and support: the child must have lived with you for more than half the year and not have provided more than half of their own support.
• Identification: the child needs a Social Security number valid for work, issued before your return's due date. Without it, the child does not count for the main credit.

How the phase-out works

The credit is generous well into the upper-middle class, but it does not last forever. Once your AGI passes $200,000 (or $400,000 if you are married filing jointly), the credit begins to taper. The reduction is mechanical: for every $1,000 of income above your threshold, and any part of a thousand counts as a whole step, you lose $50 of credit. A married couple earning $410,000 with two children sees ten steps of reduction, or $500 off their $4,400 base, leaving $3,900. Most families never reach the phase-out at all, which is why the refundable rules below usually matter more.

A worked example of the refundable part

Suppose you have three qualifying children and $20,000 of earned income, with little or no income tax owed. The base credit is three times $2,200, or $6,600, but a low tax bill means most of it cannot be used as a non-refundable credit. The refundable Additional Child Tax Credit steps in, and it is capped two ways. First, it cannot exceed $1,700 per child, here a ceiling of $5,100. Second, it is limited to 15% of earned income above $2,500. With $20,000 of earnings, that is 15% of $17,500, or $2,625. The lower of the two caps wins, so the refund is limited to about $2,625, not the $5,100 ceiling. The lesson is that earned income, not just the number of children, drives the refund for lower-income families.

Other dependents and state credits

Dependents who do not meet the under-17 test, such as a 17-year-old, a college student, or a qualifying relative you support, can still bring the $500 Credit for Other Dependents. It is non-refundable, so it reduces tax you owe but is not paid out as cash, yet families routinely forget to claim it. Separately, more than a dozen states run their own child tax credit on top of the federal one, and several are refundable, so it is worth checking your state's rules after you estimate the federal figure.

Mistakes that quietly cost families money

• Assuming the whole $2,200 per child comes back as cash. Only up to $1,700 is refundable, and only if earnings support it.
• Using take-home pay instead of AGI to judge the phase-out, which can over- or under-state the credit.
• Overlooking the $500 Credit for Other Dependents for older children and qualifying relatives.
• Confusing this credit with the Child and Dependent Care Credit, which offsets childcare costs and can be claimed alongside it for the same child.
• Letting a child's Social Security number lapse or filing after the due date without the required identification.