Monthly amount needed

Existing savings grow to
Total you will contribute
Gap the contributions must fill

How it works

Most savings calculators run forwards — you put in a monthly amount and see where it lands. This one runs backwards from the goal, which is how people actually plan: the deposit, the wedding and the school fee all have a fixed price and a fixed date.

Anything you have already put aside counts, and keeps growing on its own. The monthly figure covers only the gap left once that existing balance has done its work.

C = (Goal − P × (1 + r)ⁿ) × r ÷ ((1 + r)ⁿ − 1)

  • Goal — the amount you need at the end
  • P — what you have saved already
  • r — the monthly rate of return
  • n — the number of months until the deadline

Worked example

Needing 2,000,000 in 6 years, with 300,000 already saved, earning 8%

Inputs

Goal2,000,000
Already saved300,000
Term6 years
Return8%

Results

Monthly amount needed16,364
Existing savings grow to484,051
You will contribute1,178,214

The 300,000 already saved does 484,051 worth of work — which is why the monthly figure is far lower than dividing the goal by the months.

Frequently asked questions

What if the monthly amount is unaffordable?

Three levers: extend the deadline, lower the goal, or accept more risk for a higher expected return. Extending the deadline is usually the most effective, because it adds both contributions and compounding time.

What return should I assume for a short goal?

For anything inside three years, assume a deposit or money-market rate rather than an equity return. Money you need on a fixed date should not be exposed to a market that might be down when the date arrives.

Why is the monthly figure negative?

Because what you have already saved will grow past the goal on its own before the deadline. You do not need to add anything.

Is my data sent anywhere?

No. The calculation runs entirely in your browser. Nothing you type is transmitted to us or stored.

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