Retirement Calculator
Retirement Calculator — project savings at retirement, monthly income via the 4% rule, and year-by-year growth in 50+ currencies. Free, no signup.
Year-by-year growth
| Age | Annual contribution | Balance | Total interest |
|---|
About Retirement Calculator
The Retirement Calculator projects how much you will have at retirement and how much income that nest egg can produce. Enter your current age, retirement age, current savings, monthly contribution, and the annual return you expect — the calculator compounds monthly, applies the 4% safe withdrawal rule, and shows a year-by-year growth table. It auto-detects your currency from your location and supports more than fifty currencies, so the same maths works whether you are saving in dollars, euros, pounds, rupees, pesos, or anything else.
The 4% rule
The headline retirement-income number on the result uses the 4% rule — a planning guideline from the Trinity Study that estimates a safe withdrawal rate over a 30-year retirement. The idea is simple: in the first year, withdraw 4% of your nest egg; in every following year, withdraw last year’s amount adjusted for inflation. Historically, this approach has survived most 30-year market scenarios for diversified stock-and-bond portfolios, including the worst sequences on record. It is a planning estimate, not a guarantee — but it gives you a fast sanity check. If 4% of your projected nest egg gives you the monthly lifestyle you want, you are on a reasonable path. If not, the monthly contribution slider tells you exactly how much more you need to save.
Compound interest at retirement scale
Over a 30 or 40 year horizon, compound interest stops looking like a math curiosity and starts doing most of the work. In the default scenario — age 30 to 65, $10,000 starting balance, $500 a month at 7% return — you contribute around $220,000 over 35 years, but the projected nest egg lands close to $1 million. The other three-quarters comes from interest earning interest. That is why financial planning advice keeps repeating the same point: the return you compound matters, but the time you compound for matters more.
Why starting early matters
Time is the single biggest lever in retirement planning, and it cannot be replaced with more money later. Two examples at 7% return: save $300 a month from age 25, stop at 65, and you end up with around $720,000. Save $600 a month from age 35, stop at 65, and you end up with around $680,000 — despite contributing nearly twice as much in total. The extra decade of compounding produces more than doubling the monthly contribution can. If you are early in your career, even a small contribution starting now is more valuable than a much larger one starting a decade from now. The calculator makes this visible — change the current age and watch the final balance fall sharply.
The 25× rule of thumb
The cleanest way to set a retirement target is the 25× rule: aim for a nest egg roughly 25 times your expected annual retirement expenses. If you expect to live on $40,000 a year, target $1 million. If you expect $80,000 a year, target $2 million. This pairs directly with the 4% withdrawal rule (1 ÷ 25 = 4%) and gives you a target you can plan against from year one. State pensions, Social Security, and other guaranteed income can reduce the gap your savings need to fill, so the actual personal target is often lower than the headline number. Run your own expenses through the calculator and see what monthly contribution closes the gap.
All calculations happen in your browser. No personal data is sent anywhere. Free, no signup, no watermark — use it as often as you need to model new scenarios.
Frequently asked questions
A common rule of thumb is to save 15–20% of gross income across your working life, with a target nest egg of 25× your expected annual retirement expenses. If you expect to spend $40,000 a year in retirement, aim for roughly $1,000,000 saved. Use this calculator to back-solve: change the monthly contribution until the projected total at retirement hits 25× the income you want.
The 4% rule is a safe withdrawal guideline from the Trinity Study: in the first year of retirement, withdraw 4% of your nest egg, then adjust that amount for inflation every year after. Historically this has lasted at least 30 years for diversified stock-and-bond portfolios in most market scenarios. This calculator shows your monthly and annual income at 4% — a quick sanity check on whether your savings will support the lifestyle you want.
As early as possible. Compound interest rewards time more than amount. Saving $300 a month from age 25 at 7% return produces more at age 65 than saving $600 a month from age 35 at the same rate — the extra decade of compounding does the heavy lifting. If you have not started, the second-best time is today. Use the calculator to compare scenarios with different start ages.
Compound interest means your returns earn returns. Each month, your balance grows by the monthly rate (annual return ÷ 12), and your new contribution is added on top. Over 30 or 40 years this snowballs: most of your nest egg at retirement will come from growth, not contributions. In the default scenario (age 30 to 65, $500/month at 7%), roughly three-quarters of the final balance is interest, not money you put in.