TheCalculatory
Financial · Everyday Money Formula verified

Savings Calculator

Enter what you've already saved, what you add each month and an interest rate, and see how long it takes to hit your goal — or flip it around to solve for the monthly amount instead.

Solve for
$
$0$50k$100k
$
$0$100k$200k
$
$0$2,500$5,000
%
0%7.5%15%
On-screen number pad
Tap to type into the highlighted field
Time to reach your goal
3 years 8 months
At $300/mo
Total contributed
$18,200.00
Growth earned
$2,017.48

Step-by-step proofCheck by hand
This is a projection, not a guarantee. It assumes a constant interest rate and constant monthly contributions, which real savings accounts and market-linked accounts rarely deliver exactly. Rates change, and any account beyond a basic savings account carries some risk of loss. This is not financial advice.
Visual breakdown

Contributed vs. growth

Contributed Growth

The bar shows what you put in versus what interest added, as shares of the balance when the goal is reached — the same two numbers as the result panel, drawn to scale.

How this is calculated

Each month, interest is added to whatever is already in the account, then that month's contribution is added on top — the same monthly-compounding order the Compound Interest Calculator uses, just run one month at a time until the balance reaches your goal.

There's no algebra shortcut for "how many months" when both a starting balance and a recurring contribution are involved, so this simulates the account month by month rather than solving a formula directly. "Monthly amount needed" works the same way in reverse, narrowing in on the contribution that hits the goal by the date you set.

A projection, not a promise
This assumes the rate and the monthly contribution stay exactly constant. A real savings or investment account's rate moves, and contributions rarely land on the same day every month — treat the result as a planning estimate, not a guarantee.
Compare with Compound Interest
If you already know how many years you're saving for and want the projected balance, the Compound Interest Calculator answers that more directly.

The method

balance += balance × (rate ÷ 12)  →  balance += monthly contribution  (repeat monthly)

"Time to goal" repeats this until the balance meets the goal; "monthly amount" searches for the contribution that does.

Worked example

Starting from $5,000, adding $300 a month at a 4.5% APY: the balance passes $20,000 after 44 months — 3 years and 8 months — with $18,200 of that coming directly from contributions and the remaining $2,017.48 from interest.

Frequently asked questions

Why does the same monthly amount reach different goals at different speeds?
Because growth compounds on whatever is already in the account, so a larger starting balance or a higher rate accelerates faster than the linear sum of deposits alone would suggest. The last few months toward a goal are usually reached faster than the first few, because more of the balance is earning interest by then.
How is this different from the Compound Interest Calculator?
Compound Interest projects the balance forward from a fixed number of years. This calculator solves it the other way around — starting from a target dollar amount, it works out how many months it takes to get there, or how large a monthly contribution has to be to arrive by a specific date. Same underlying math, a different question.
What interest rate should I use?
Use the actual annual percentage yield (APY) on the account you're using, not an assumed market return. A high-yield savings account might currently pay in the low single digits; a brokerage account invested in the market has no guaranteed rate at all and should be modeled with a range of scenarios rather than one number — see the Investment Calculator.
Does this account for taxes on interest earned?
No. Interest earned in a standard savings account is generally taxable income in the year it's earned (outside a tax-advantaged account like a TFSA or Roth IRA), which this calculator does not subtract. Your actual after-tax growth will be somewhat lower than the figure shown here.
Sources and method
  • Monthly-compounding projection — the same published compound-interest mathematics as the Compound Interest Calculator, applied month by month rather than year by year.
  • Time-to-goal and required-contribution figures are solved numerically (iterative simulation / bisection search), since neither has a closed-form solution when both a starting balance and a recurring contribution are present.
Last reviewed: 19 Sep 2026 Sources last verified: 19 Sep 2026 Results use the assumptions explained on this page. Report an error How we check calculations

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