Does it account for interest?

Yes. It applies your annual interest rate with monthly compounding to both your starting balance and your ongoing contributions.

Why does it say my goal is not reachable?

With a zero or very small monthly saving and zero interest, the goal can never be met. Increase your monthly amount or interest rate and the timeline will appear.

Does my starting balance count towards the goal?

Yes. Your existing savings are grown at the interest rate over the period, and only the remaining gap is split into monthly contributions — so the more you start with, the less you need to save each month.

How is the time-to-reach mode calculated?

It solves the annuity equation for the number of months, taking into account interest on both your starting balance and your ongoing deposits. The result is shown as years and months.

What interest rate should I enter?

Use the rate your account actually pays. For an instant-access savings account that might be 3–5%; for a cash ISA or fixed bond it could be higher. Set it to 0 if you are saving in a non-interest account.

Is my savings information uploaded?

No — every calculation happens entirely in your browser and nothing you enter leaves your device.

Savings Goal Calculator

Savings goal calculator

Set a target and this calculator works backwards to your plan. In monthly mode it tells you how much to set aside each month to hit the goal in a fixed time; in time mode it tells you how long a chosen monthly amount will take. Either way it factors in what you have already saved and the interest your balance earns. It is for anyone saving towards a deposit, a holiday, an emergency fund or any fixed target with a deadline.

How it works

The calculator compounds monthly at rate i = annual% ÷ 12 ÷ 100. Your starting balance grows to start × (1 + i)^n over n months, and the rest of the goal is covered by an annuity of deposits.

Required monthly saving: grow the starting balance, find the remaining gap, then divide by the annuity factor ((1 + i)^n − 1) ÷ i to get the deposit.
Time to reach the goal: solve n = ln((goal × i + PMT) ÷ (start × i + PMT)) ÷ ln(1 + i).

If your starting balance plus its growth already covers the goal, the required saving is zero.

Example

Goal 20,000, already saved 2,000, at 3% interest over 36 months. The 2,000 grows to about 2,188, leaving roughly 17,812 to fund. Divided by the annuity factor this needs about 474 per month.

Goal	Starting	Rate	Months	Required / month
10,000	0	3%	24	405
20,000	2,000	3%	36	474
5,000	1,000	0%	12	333

All maths runs in your browser, so your savings figures stay private.