What this calculator works out
This calculator takes a target, what you have already put aside and what you can save each month, and returns how long the goal will take. It also converts the monthly figure into a weekly equivalent, which is often the more useful number to hold in your head.
It deliberately ignores interest. For a goal measured in months rather than decades, interest changes the answer very little, and leaving it out means the result is a floor rather than an optimistic projection.
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Before you set the target
- Use the full cost, not the headline price. A car includes insurance, tax and the first service; a holiday includes transfers, food and spending money; a kitchen includes fitting and making good.
- Set the monthly figure at what you can sustain in an ordinary month, not a good one. A plan you abandon in month four is worse than a slower plan you keep.
- Check the target date is not fixed by something outside your control. If it is a wedding or a lease expiry, work backwards from the date instead and see whether the required monthly figure is realistic.
- Keep goal money separate from your emergency fund. They do different jobs and raiding one for the other defeats both.
Monthly amounts are easy to agree to and hard to feel. £100 a month is £23.01 a week, which is a decision you can recognise — a takeaway, a round of drinks, two coffees a day. Goals are met or missed at the weekly scale, not the monthly one.
How this calculator works
Three straightforward steps:
Remaining = target − already saved
Months = remaining ÷ monthly saving, rounded up
Weekly equivalent = monthly saving ÷ 4.345Months are rounded up because a partial month does not reach the target — if you need 8.2 months of saving, you arrive in month nine.
The weekly conversion uses 4.345 rather than 4, because a year has 52.18 weeks rather than 48. Dividing by 4 would understate the weekly amount by roughly 8%.
Worked example: a £1,000 goal
Using the default figures — a £1,000 target, £100 already saved and £100 a month:
- Remaining: £1,000 − £100 = £900
- Time: £900 ÷ £100 = 9 months
- Weekly equivalent: £100 ÷ 4.345 = £23.01 a week
If nine months is too long, the arithmetic offers exactly three levers and no others: raise the monthly amount, lower the target, or accept the date. Reducing the target to £800 brings it to seven months; raising the monthly figure to £150 brings it to six. Seeing the three options side by side is usually more useful than the original answer.
Common mistakes
- Setting the target at the advertised price. The extras are what push a goal past its date.
- Choosing a monthly figure based on a good month. Sustainability beats ambition over a nine-month horizon.
- Saving into the current account. Money that sits alongside spending money gets spent. Use a separate account.
- Running several goals at once from the same surplus. Three goals sharing one monthly amount take three times as long each, and all three feel stalled.
- Forgetting the goal will cost more by the time you reach it. On anything more than a year away, add an allowance for price rises.
Frequently asked questions
Why does this ignore interest?
Because over the timescales most goals occupy, it is close to irrelevant. £900 saved over nine months in an account paying 4% earns roughly £15 — real, but not enough to change any decision. Excluding it means the timescale shown is the one you will actually experience rather than a best case.
What if I have a fixed deadline instead of a fixed monthly amount?
Divide the remaining amount by the number of months available to find the monthly figure required, then judge whether it is realistic. If it is not, the deadline or the target has to move — and finding that out now is considerably better than finding out in month seven.
Should I save for a goal or clear debt first?
Generally, clear debt charging more interest than your savings earn. A credit card at 24% costs far more than a savings account pays, so the arithmetic favours the debt. The exception is a small starter buffer, which is worth holding first so that an unexpected cost does not put you straight back onto the card.
How do I stop dipping into it?
Distance and friction. Use a separate account, ideally with a different provider so it is not visible when you check your balance, set up a standing order for the day after payday, and do not hold a card for it. Some accounts allow notice periods, which adds useful delay.
Is my goal stored?
No. Everything you enter is processed in your browser and nothing is transmitted or retained as a record.
Related tools
References
- MoneyHelper — guidance on setting savings goals and choosing a savings account
- Bank of England — Bank Rate, which drives the interest rates offered on savings accounts
Sources are checked at publication and can change — how I choose and check references.