Savings Goal Calculator
Work backwards from the number you actually need. Set a target and a date and this gives the monthly contribution; set a contribution instead and it gives the date. Interest is compounded monthly throughout.
Your Goal
Choose what you want solved; the other field becomes the answer.
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Saving toward a date is a different problem from saving in general
Most savings advice answers “how much will this grow to?”. A goal asks the reverse: given the number and the deadline, what does that require of me every month? That inversion changes behaviour, because the answer is a single figure you can either afford or cannot.
Why the interest rate matters less than you would hope
Over short horizons, contributions dominate and interest is a rounding error. Saving $300 a month for three years puts in $10,800; at 4% the interest adds roughly $680 — about 6% of the total. Over twenty years the balance flips and growth does most of the work. Check the growth share figure: if it is small, chasing a slightly better rate is not where your effort should go.
Match the account to the horizon
Money needed within about three years does not belong in anything that can fall in value. A high-yield savings account or a short certificate of deposit keeps the number certain. Money with a ten-year horizon can tolerate volatility in exchange for a higher expected return — but the rate you enter should then be an expectation, not a promise.
How the maths works
This is the future value of an ordinary annuity with a lump-sum start:
FV = PV(1 + i)n + PMT × ((1 + i)n − 1) / i.
Solving for PMT rearranges it; solving for n uses
logarithms, falling back to a month-by-month search when the rate is zero.