Monthly contribution needed to hit a goal when you've started late.

If you have 20,000 saved, want 100,000 in 10 years, and expect a 7% annual return, your existing pot grows to roughly 39,300. The 60,700 gap needs about 366 a month of new contributions to close.

How to use it

Enter what you have now, what you want to reach, the years remaining, and a realistic return rate. Cash savings rates are typically 2-5%; diversified long-term equity portfolios average 5-8%; higher assumptions carry higher risk.

What the result means

The primary figure is the monthly contribution needed. The secondary rows show your existing pot's projected growth, the gap new contributions must close, and total new money added over the period. If the monthly figure looks too high, the options are: extend the time horizon, lower the target, or raise the assumed return (but be realistic — higher return assumptions carry higher risk of not being hit).

What this doesn't model

Inflation. The target is treated as a nominal figure. To plan for real purchasing power, reduce the assumed return by your inflation expectation or uprate the target by the same amount.

Run it with sensible defaults

Using current savings of 20,000, target amount of 100,000, years remaining of 10 years, annual return of 7%, the calculation works out to 365.85. Nudge the inputs toward your own situation and the output recalculates instantly. The defaults are meant as a starting point, not a recommendation.

The levers in this calculation

The inputs — Current Savings, Target Amount, Years Remaining, and Annual Return — do not pull with equal force. Not every input has equal weight. Flip one at a time toward extreme values to feel which ones move the needle most for your situation.

How the math works

Projects the current pot forward at the annual return, subtracts from the target to find the gap, then solves the ordinary annuity formula for the annual contribution needed to fill the gap and divides by 12 for the monthly figure. Assumes end-of-year contributions and annual compounding. The working is transparent — you can verify every step yourself in the formula section below. No black box, no opaque "proprietary model".

Turning the result into a plan

A projection is just a starting point. The real work is setting the monthly amount aside automatically so the saving happens before you can spend it. Most people who hit savings goals set up a standing order on payday; most who miss them rely on willpower at month-end.

What this doesn't capture

The calculation assumes a steady savings rate and a stable interest rate. Real saving journeys include emergencies, windfalls, and rate changes — especially in easy-access products. The figure is a direction of travel, not a guarantee.