College Savings Calculator

Time in the Market Beats Timing the Market

The gap between what a family contributes to a college fund and what actually ends up available by freshman year is compound growth — and that gap widens dramatically the earlier contributions start. A modest monthly deposit made consistently for fifteen years can outperform a much larger one started five years before enrollment. This calculator projects the future value of a college savings account given a starting balance, a recurring monthly contribution, an expected rate of return, and a time horizon.

The Formula

FV = P(1+r)n + PMT × [((1+r)n − 1) / r]

P is the initial savings balance, PMT is the monthly contribution, r is the monthly interest rate (annual rate divided by 12 and converted to a decimal), and n is the total number of months. The first term grows the starting balance; the second term is the future value of the recurring monthly contributions.

A Worked Example

$5,000 initial savings, $200/month, 6% annual return, 10 years
ComponentValue
Total Contributed ($5,000 + $200 × 120 months)$29,000.00
Total Interest Earned$12,872.85
Future Value$41,872.85

Interest earned makes up roughly 31% of the final balance in this example — a meaningful boost over simply saving the same amount in cash.

Where This Calculation Matters

  • Setting a savings target — working backward from a projected tuition cost to figure out what monthly contribution actually gets there.
  • Comparing savings vehicles — running the same contribution schedule at different expected rates of return to compare a savings account against an investment account.
  • Starting-age tradeoffs — showing concretely how many more years of growth are lost by waiting to start saving.
  • Grandparent or relative contributions — modeling the effect of a lump-sum gift added to an existing plan.

How to Use This Calculator

  1. Enter the Initial Savings amount already set aside.
  2. Enter the Monthly Contribution you plan to add.
  3. Enter the expected Annual Interest Rate as a percentage.
  4. Enter the Years Until College the money has to grow.
  5. Select Calculate to see the projected future value, total contributed, and interest earned.

Related Calculations

For the tax-advantaged version of this same math, see the 529 Plan Growth Calculator, or project how much that savings will need to cover with the Tuition Cost Calculator.