Savings Goal Calculator

Enter your goal, current savings, months, and expected annual rate to get the exact monthly deposit that hits your target on time.

All calculations happen locally in your browser. Nothing leaves your device.

Save per month
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Total deposits
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Total interest
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Time to goal
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Assumes a constant annual rate compounded monthly and no fees or taxes. A planning estimate, not financial advice.

How It Works

Instead of guessing, this tool does the arithmetic for you. It takes your goal, what you already have, the number of months you have, and an expected annual return — then works out the single monthly amount that lands exactly on your goal on time, with interest doing part of the work.

Monthly compounding, month by month
The annual rate is converted to a monthly rate (rate ÷ 100 ÷ 12). Every month your balance first grows by that interest, and then your fixed deposit is added on top. This is repeated for the full horizon, exactly the way most savings accounts compound.
Finding the exact monthly amount
The smallest deposit x such that the balance reaches at least your goal after the final month is computed directly: x = (goal − current × (1 + r)^n) × r ÷ ((1 + r)^n − 1), with a simple (goal − current) ÷ n division when the rate is zero. The result is then verified by simulating every month, so the numbers you see are the true trajectory.
What interest changes
The "Total interest" figure shows how much of your final balance is earned rather than deposited. The longer your horizon and the higher your rate, the bigger that slice — which is the whole point of starting early and keeping money in a growing account instead of under the mattress.

Frequently Asked Questions

How is the monthly savings amount calculated?

The tool works month by month with compound growth. Each month your balance grows by the monthly interest (annual rate ÷ 100 ÷ 12) and then you add a fixed amount x. The smallest x that brings the balance to at least your goal after the exact number of months is reported. The result is verified by simulating every single month, so what you see is the real trajectory of your savings.

What does the 'Total interest' number mean?

It is the amount your savings earn over the whole period, assuming the stated annual rate is constant. Your final balance equals what you already have plus everything you deposit plus the interest earned on the way. A higher rate or a longer horizon turns more of the goal into interest instead of deposits.

What if I already have more saved than my goal?

If your current savings already meet or exceed the goal, the calculator shows $0.00 per month — the goal is effectively already reached. Lower the goal, or keep the numbers to see how interest alone would grow what you already have.

Does this include fees, taxes or inflation?

No. The calculation is a clean mathematical model: a fixed monthly deposit plus a constant annual return. Account fees, taxes on interest, contribution limits and inflation are not modeled — use the result as a planning estimate and adjust for your real account terms.

Is this accurate?

The math is exact for the inputs you give: monthly compounding, fixed deposit, constant rate. Real results vary with compounding conventions (some accounts compound daily or annually), changing rates, fees and taxes. This tool is a planning aid, not financial advice — the numbers are estimates based on the assumptions you enter.