Saving & Investing
Savings Goal Calculator
Set a target and a deadline, and find the monthly deposit that gets you there — with interest on the balance doing part of the work.
Deposit needed each month
$492.83
$5,914 a year for 5 years
- Projected balance at deadline
- $40,000
- Total you deposit
- $29,570
- Interest earned
- $4,430
- Shortfall if you deposit nothing
- $32,674
Where the target comes from
- Already saved — 15%
- New deposits — 74%
- Interest — 11%
How the required deposit is found
First the calculator grows your existing balance forward to the deadline. Whatever gap remains has to come from deposits, so it divides that gap by the future-value factor of a monthly annuity — ((1 + r)^n − 1) ÷ r, where r is the monthly rate and n the number of deposits.
The consequence is that the required deposit falls sharply as the horizon lengthens, and far more sharply than the interest rate assumption changes it. Buying yourself an extra year is usually worth more than chasing an extra percent of return.
Taxes on interest and any account fees are not modelled. For a goal you cannot miss — a house deposit or a tax bill — plan with a rate at or below what a savings account pays.
Frequently asked questions
What rate should I use for a short goal?
For a target within two or three years, use a cash or savings-account rate. Market returns are too volatile to rely on over short horizons.
Why is the required deposit sometimes zero?
Because the balance you already have grows enough on its own to reach the target in the time available.
Does the calculator assume deposits at the start or end of the month?
End of the month, which is the conservative assumption. Depositing at the start would reach the goal marginally sooner.
Should I include an emergency fund in the target?
Keep it separate. An emergency fund is money you must not invest in anything volatile, so it usually needs a different rate assumption.