Savings Goal Calculator — how long to reach my target
Enter a savings target, what you already have, your monthly deposit and an interest rate. Get the month you reach it, how much came from interest, and what you would need to save monthly to finish in 3, 5 or 10 years. Runs entirely in your browser.
The compounding model, and where it lies
How long it takes, or how much a month
“I want to save 50,000, I have 3,000, I can put away 500 a month — when does the day actually arrive?” Guessing is unreliable because each monthly deposit starts earning interest at a different moment, so the later money barely compounds at all.
The top three boxes answer what happens if I keep going like this. The bottom three invert it: what monthly deposit would be required to finish in 3, 5 or 10 years. Most people lower the target after reading that second row, which is usually more honest than promising to save money you do not have.
How it computes
- Deposits are credited at the end of each month (an ordinary annuity), so the first deposit earns exactly one month of interest.
- The annual rate is divided by 12 and compounded monthly. A rate of 0 degrades to plain addition — useful as a worst case.
- Money you already have compounds along with the deposits.
- “Time to target” steps month by month until the balance first reaches the target, so you never get an answer like “2.3 more months”.
Where this model lies to you
- Inflation. 50,000 in ten years is not 50,000 today. If that bothers you, inflate the target before entering it.
- Rates move. Real accounts reset every term; this uses one frozen assumption.
- Withdrawals happen. Any unplanned draw means recalculating from the new balance, not “catching up later”.
- Fees and tax are not deducted anywhere here.
Frequently asked
What rate should I enter? If it sits in a savings account or money-market fund, 0.5–2%. Anything above 3% should make you ask whether that return is actually guaranteed. When unsure, enter 0 and treat the result as the worst-case deadline.
Why does it say I will never reach it? The deposit is too small relative to the target. The “to finish in 10 years” box tells you the size of the gap.
I already have a lump sum and no monthly deposit — does that work? Yes. Set the monthly deposit to 0 and the result is driven purely by compounding on what you have.