Everyone has a number they want. Almost nobody knows the monthly payment behind it. This runs the maths backwards: you name the amount and the year, and it tells you what it takes each month, starting now.
Your goal
Work backwards: pick the amount you want, then find the monthly payment that gets you there.
Nobody knows the future. Lower is the safer guess.
Fill this to see how close your current amount gets you.
What this tool does
Most calculators run forwards: you put in a monthly amount and they tell you what it becomes. This one runs backwards. You name the amount you want and the year you want it, and it tells you the monthly payment that gets you there.
That is a more useful question, because the goal is usually the fixed part. You know you want to buy the shop, cover the rent forever, or stop needing a salary. What you do not know is the monthly number that makes it real.
When you should use it
When you have a target — a house deposit, a business, a freedom number — and no plan behind it.
When you want to know if a goal is realistic before you promise it to your family.
When you get a raise and want to point the extra somewhere.
To compare timelines: the same goal in ten years versus twenty is a very different monthly payment.
How to read the answer
The monthly amount — what it takes, starting now. It rises fast every year you delay, which is the whole lesson.
You put in / growth added — how much of the final pile is your own money and how much the returns did. Over long periods the second number overtakes the first. Over short periods it never does, so a five-year goal is mostly saving, not investing.
If you can only manage X — the honest version. It shows what your current amount actually reaches, and how many more years the goal would need.
Inflation view — if you switch it on, the answer is in today's money. A hundred thousand in twenty years does not buy what it buys now.
Example. Goal 100,000 in 15 years, starting with 2,000, assuming 7% a year. The monthly amount is around 300. Wait five years and the same goal needs roughly double. The number that changes most is not the return — it is the time you gave it.
What this tool cannot tell you
It cannot promise a return. Markets do not deliver a smooth 7% every year; they deliver good years and frightening ones that average out over decades.
It ignores fees and tax, both of which quietly eat returns. Assume the real result is a little lower.
It assumes you keep paying every month, including the months when it hurts. That assumption breaks more plans than bad markets do.
It says nothing about where to invest. That depends on your country, and no calculator should decide it for you.
It is not advice. Nothing you type is sent anywhere or saved.
Common questions
How much should I invest every month?
There is no universal number. Work backwards from a goal, as this tool does, and then check the answer against your budget. If the two do not meet, either the goal moves, the timeline stretches, or the income has to grow.
What return should I assume?
For long periods, a broad stock market has historically averaged somewhere around 7% a year after inflation, but with heavy swings. For anything under five years, assume much less, because a bad year has no time to recover.
Is it better to invest a lump sum or monthly?
If you already hold the money, investing it sooner has usually won historically. But monthly investing is what most people actually have, and it removes the pressure of picking the right day.
Why does starting five years earlier change so much?
Because growth compounds on growth. The early payments have the longest time to multiply, so they do the heaviest lifting. Time is the one input you cannot buy back later.
Next step
Not sure how much you can spare each month? Split your income first, then come back with a real number.