Retirement Calculator 🔒 Your data never leaves your browser.
Project your retirement savings balance from age, contributions and returns.
About this tool
This retirement calculator projects how your savings could grow between now and retirement, given a starting balance, a steady monthly contribution and an expected annual return. Rather than approximating with a single formula, it simulates the balance month by month — applying the effective monthly rate implied by your annual return and adding your contribution at every step — so the projected balance, total contributed and total investment growth figures all reflect what actually happens to the money over the whole period.
Keep in mind this is a simplified planning estimate, not financial advice. Real markets don't return the same percentage every year — they swing up and down even when long-run averages hold — so an actual outcome will look bumpier than this smooth projection. The numbers also ignore inflation eroding future purchasing power, and don't model the rules of tax-advantaged accounts such as 401(k) contribution limits or employer matching. Use it to sanity-check your savings rate, not to plan your finances down to the dollar. Everything runs locally in your browser; no numbers are ever sent anywhere.
Frequently asked questions
Why does starting 10 years earlier make such a huge difference to my final balance?
This is compound growth at work: money invested earlier has more time periods to earn returns, and — crucially — those early returns themselves start earning their own returns. Ten extra years at a typical 7% return roughly doubles the growth multiplier on that early money, so a relatively small amount contributed in your 20s can end up outgrowing a much larger amount contributed later in your 30s or 40s, purely because of the head start.