How a savings goal is calculated

The goal in one paragraph

A savings goal is a balance you want by a date, not a story about what the market will do. The savings goal calculator grows what you already have, adds a monthly deposit at the end of each month, and tells you two things: the balance you are on track to hold, and the deposit that would land exactly on the target if the rate stays put.

When to use

Use it when the question is “will this monthly amount get me there?” A house down payment, a tuition bill, or a move all fit. It is the wrong tool for the cash you must not invest — that is the emergency-fund guide — and the wrong tool for what the balance will buy after prices rise. That is the inflation guide.

The formula in plain English

FV = PV×(1+r)^n + PMT×[((1+r)^n − 1) / r]
r = annual rate / 12
n = years × 12

PV is money already saved. PMT is the deposit at the end of each month. r is the annual rate divided by 12. The required deposit rearranges the same equation so the future value equals the goal. If the rate is zero, the balance is simply today’s savings plus every deposit. If today’s savings already compound past the goal, the required deposit is zero.

The calculator on this site runs that math in your browser. Nothing you type is sent to a server to compute the result.

A worked example

Start with 10,000, add 200 a month, and earn 0% for 5 years. You deposit 12,000 of new money and finish at 22,000. The deposit that hits a 22,000 goal on that path is 200 a month, and the timeline is 60 months. Turn the rate up and any amount above 22,000 is interest, not cash you added.

How to read the result

The projected balance is a projection. The shortfall is the goal minus that balance. The required monthly amount is the deposit that closes the gap on the horizon you set, not a bill you must pay. Months to the goal walk forward until the balance crosses the target, and they stop reporting after 100 years.

Scenario B is a second plan. Keep the years identical if you want the gap to be about the deposit or the rate.

Common mistakes

Treating the ending balance as a forecast. The rate is an assumption you typed.

Comparing two horizons and calling the difference a savings-rate effect. Extra years do their own work.

Ignoring inflation. A nominal goal can be met while buying less than you pictured. The inflation calculator is the place for that question.

FAQ

Does the required deposit include money I already saved?

No. The current balance is grown first. The required deposit is only the monthly amount that covers what is left.

Why can the required deposit be zero?

If the savings you already have reach the goal by compounding alone, no new deposit is required under these assumptions.

Are taxes or inflation included?

No. This page is nominal. Open the inflation calculator for purchasing power. Taxes sit outside both tools.

What if the goal is never reached?

The months line says so after 100 years. A zero contribution and a zero rate cannot close a gap. Raise the deposit or the horizon.

Does the page choose the return?

No. Fed funds fills the custom annual return from the official target-range midpoint, and you can still edit the field. The link stores the number you apply. Indicative rate, not a recommendation.

Is this financial advice?

No. The guide and the calculator illustrate the formula. They do not know your taxes, fees, or whether the rate will happen.

Related guides

• How big an emergency fund should be — the cash reserve to fund before a longer goal.
• Inflation, IPCA, and real return — what a nominal balance buys after the inflation rate you type.
• How much home you can afford — turn a down-payment goal into a housing budget.
• How compound interest actually works — the same monthly engine, aimed at the ending balance.

Try it with your figures

Open the savings goal calculator, set the target, what you already saved, and the monthly amount. Share the URL if you want the same inputs again — the numbers stay in the link, not on a server.