Kids' investment calculator
See what $25 or $50 a month from birth grows into by age 18, or by 30 if it keeps going.
At age 18
From $10,800 put in. Left alone after that, it could be $48,503 by 30 and $517,850 by 65.
Children can invest through a custodial account (UTMA/UGMA), a 529 plan for education, or a Roth IRA once they have earned income. New government-backed children's accounts launched in the US in 2026; check current rules.
How this calculator works
The calculator invests your monthly amount from your child's current age until the age you choose, then shows what happens if the money is simply left to grow.
Starting at birth gives the money the most years to compound, which matters more than the amount.
Common questions
What accounts can I use?
Common options are a custodial account (UTMA/UGMA), a 529 plan for education, and a Roth IRA once the child has earned income. Government-backed children's accounts were introduced in the US in 2026; check current rules.
Who controls the money?
In a custodial account, the child gets control at the age of majority in your state, often 18 or 21.
Are there taxes?
Investment income in a child's name can be taxed at the parent's rate above a small amount (the "kiddie tax"). 529 growth is tax-free for qualified education costs.
FatDCA calculators are educational estimates, not investment, tax or legal advice. Results depend on the assumptions you enter, and past returns do not predict future returns.
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