Quick answer
A savings goal calculator works backwards: it tells you the monthly deposit needed to reach a target by a deadline. To reach $30,000 in 5 years starting from $5,000 at a 4% return, you need to save about $360 a month.
How the Savings Goal Calculator works, step by step
The tool runs in two modes. Monthly mode solves for the deposit: enter the target, what you have saved, the expected return and the deadline, and it returns the monthly amount that gets you there. Time mode works the other way: enter the monthly amount you can actually afford and it simulates month by month until the balance reaches the goal, or warns you if it never does.
The monthly figure comes from growing your existing savings forward, subtracting that from the target, and solving for the deposit that covers the rest with interest. If your savings already cover the goal, the required deposit is zero. The tool also shows your progress as a percentage of the goal, so a $5,000 start on a $30,000 target reads as 16.7% funded before the first new deposit lands.
The return assumption should match where the money will sit. For a goal under 3 years away, that is a savings account rate — top high-yield accounts paid about 4.2% to 4.4% APY in November 2026. Investing a short-term goal in stocks can leave you short exactly when the money is due, because a market fall near the deadline has no time to recover.
Read the output as a budget line, not a wish. If the required deposit does not fit your budget, the honest levers are a later deadline, a smaller target, or a lump sum added now — each month of delay raises the required deposit because there is less time for both deposits and growth. Money added today is worth more than the same money spread out: $2,000 added now at 4% is worth about $2,443 in 5 years.
For goals priced in today's money — a house deposit, a car, a wedding — remember the target moves while you save. Either raise the target by roughly 3% per year of waiting, or use a return net of inflation in the calculator. House deposits are the classic case: the price of the house, and therefore the deposit, rises while the savings plan runs.
The formula
Monthly deposit = [Target − Saved × (1 + r/12)^(12t)] × (r/12) / [((1 + r/12)^(12t)) − 1], where r is the annual return and t the years to the deadline.
Worked example — try it on the calculator above
Worked example: $30,000 house deposit in 5 years
You have $5,000 saved and the money earns 4% a year. The $5,000 grows to about $6,105 in 5 years, leaving $23,895 to come from deposits and their earnings. The required deposit is $360.41 a month — call it $361. Total deposits come to $21,625, and interest supplies the remaining $3,375 of the target. Switch to time mode with $500 a month instead and the goal is reached in just 45 months, a year and a quarter early.
Frequently Asked Questions
What if I save weekly or every payday instead of monthly?
Convert to a monthly equivalent: a deposit every two weeks happens 26 times a year, so multiply it by 26 and divide by 12. Saving $167 every payday is about $362 a month. More frequent deposits earn marginally more because the money arrives sooner on average.
Should I include inflation in my target?
For goals priced in today's money — a house deposit, a car, a wedding — yes, if the price is likely to rise. Either raise the target by roughly 3% per year of waiting, or use a return net of inflation in the calculator. House deposits are the classic case: the target moves while you save.
What return should I use for a goal 10 or more years away?
A balanced portfolio assumption of 5% to 7% is common for long horizons, but the result is an estimate, not a promise. Run the calculation at a lower return as well; if the plan only works at the optimistic rate, the deposit is too small.
Is it better to add a lump sum or raise the monthly deposit?
Mathematically, money added earlier is worth more because it compounds for the whole period. $2,000 added today at 4% is worth about $2,443 in 5 years; the same $2,000 spread as extra deposits arrives later and grows less. If a bonus or tax refund is available, front-loading wins.
Estimates, not advice. This calculator provides educational estimates based on the inputs you enter and the assumptions shown on this page. It is not financial, tax or investment advice, and it cannot see your full situation. Verify important figures against official sources, and consider a qualified professional for decisions about your own money. See our Disclaimer and Methodology.