Savings Goal Calculator

Most growth tools ask what you will put in and tell you where you end up. This one works the other way: you name the amount and the deadline, and it tells you the monthly deposit that gets you there.

It assumes you deposit the same amount at the start of every month and that the balance grows at your annual return ÷ 12 each month. With the defaults, reaching $1,000,000 in 15 years at 7% takes $3,136.65 a month. Over 180 deposits you put in $564,597.40. The remaining $435,402.60 is growth, which the tool doesn't list separately.

Here is the same $1,000,000 goal with one input changed at a time.

Adding five years cuts the deposit far more than adding two points of return, and time is the input you control. The return is an assumption. The 0% row is useful as a floor: it is what the goal costs if the money earns nothing.

There is no box for a starting balance, so account for it yourself.

1. Work out what your current savings grow to by the deadline at the same return. $50,000 at 7% for 15 years, compounded monthly, becomes about $142,447.34. The investment calculator, with a $0 monthly contribution, gives the same figure.
2. Subtract that from the goal: $1,000,000 − $142,447.34 = $857,552.66.
3. Enter the reduced goal here. The monthly deposit falls from $3,136.65 to $2,689.84.

The goal is a future amount. If what you want is today's spending power, raise the goal for inflation first. With an assumed 3% a year, matching today's $1,000,000 in 15 years takes about $1,557,967.42. Enter that as the goal.

For short goals, the return assumption barely matters, and it should match where the money will actually be kept. Saving $20,000 in 3 years at 4% takes $522.07 a month, against $555.56 at 0%. A house deposit or a car fund is mostly built from your own deposits, not growth.