Your savings plan
How long until you reach your savings target?
Your savings plan
A savings goal calculator answers a single question: given a target amount, a starting balance, and an expected return rate, how long until I get there — and how much do I need to save each month?
It uses the future value of an annuity formula in reverse. You provide the goal (FV), starting amount (PV), expected rate (r), and time horizon (n) — the calculator solves for the monthly contribution required. Or you fix the monthly contribution and solve for time.
Two practical takeaways: (1) the higher the rate, the lower the monthly burden — at 1% interest the same goal would require ~$590/month. (2) Starting balance matters more for short horizons than long ones — a 5-year head start of $5,000 saves you about $96/month here.
Most savings goals fall into three time-horizon buckets, each with its own appropriate vehicle and return assumption:
| Horizon | Examples | Vehicle | Realistic return |
|---|---|---|---|
| <1 year | Emergency fund, holiday | High-yield savings | 4–5% |
| 1–5 years | House deposit, wedding, car | Term deposit / mixed fund | 4–6% |
| 5+ years | Retirement, kids' education | Index fund / KiwiSaver | 6–8% |
Important: never put short-horizon money in volatile investments. A "5% expected return" from stocks is an average over decades, not a guarantee for any specific year. House deposits parked in equities have ruined many home-buying timelines.