How this retirement calculator works
The calculator runs two simulations side by side. First, it grows your current savings plus your monthly contributions at your expected return rate, month by month, until you hit your target retirement age — that's your projected nest egg. The underlying math is the same compound interest formula you can explore in detail in our compound interest calculator. Second, it estimates how big that nest egg needs to be to fund your desired annual lifestyle, adjusted for inflation, for as long as you plan to be retired. The difference tells you whether you're on track or have a gap to close.
Most retirement calculators just give you a single number. This one shows the surplus or shortfall directly, plus a concrete action — increase your monthly contribution by €X or delay retirement by Y years — so you can see exactly which lever moves the needle for your situation.
How much do I actually need to retire?
The honest answer: it depends on your lifestyle, your country's social safety net, and how long you live. But there are well-tested rules of thumb that get you in the right ballpark.
The 25× rule
The most common shortcut is: aim for 25 times your desired annual spending. So if you want €35,000/year in retirement, you'd want roughly €875,000 saved by the day you stop working. The math comes from the "4% safe withdrawal rate" — the idea that withdrawing 4% of your portfolio each year, adjusted for inflation, has historically lasted 30+ years in almost every market scenario tested.
It's not a guarantee. The 4% rule was based on US data from 1926 onward, and starting your retirement in a particularly bad year (2000, 1966, 1929) tested it severely. But as a planning anchor, it's still the most widely-used number in personal finance.
Adjusting for your situation
- If you're in a high-tax country — your gross withdrawal will need to be higher to net the spending you want. A 4% withdrawal at 30% effective tax means you need a 5.7% gross withdrawal, which means you need a bigger pot (roughly 30× spending, not 25×).
- If you'll have state pension or social security — subtract that from your "needed from portfolio" figure. In the Netherlands, the AOW provides a baseline; in Belgium, the wettelijk pensioen; in Germany, the gesetzliche Rente. Even modest state benefits dramatically reduce the size of the private pot you need.
- If you'll retire before 60 — your money has to last longer, and you can't yet access tax-advantaged pension wrappers. Many FIRE-style plans aim for 28×–33× spending instead of 25× to compensate.
- If your house is paid off by retirement — your spending in retirement is often 20–30% lower than your current spending. The calculator's "desired income" field should reflect retirement expenses, not today's.
The four levers that move retirement readiness
If the calculator shows a shortfall, you have exactly four levers to pull. Most people pull one and ignore the rest — but the biggest wins come from combining them.
1. Save more each month
The most obvious lever, and often the most painful. But because of compounding, the impact of an extra €100/month is dramatically larger when you're early in your career. €100/month from age 30 to 65 at 7% returns becomes around €180,000 by retirement. The same €100/month starting at age 50 becomes around €31,000. Same effort, six times the result, just because of the compounding runway. If you want to work backwards from a specific shortfall — "how much extra per month do I need to close a €X gap by year Y?" — our savings goal calculator solves exactly that question.
2. Earn a higher return
The difference between 5% and 7% over 35 years isn't a "bit" more money — it's often double. But chasing higher returns has a real cost: more volatility, more sleepless nights, and a higher chance of panic-selling at the worst possible moment. For most people, the right move isn't "find higher returns," it's "stop sabotaging the returns you'd get from a basic globally-diversified index fund" by paying high fees, trading too often, or trying to time the market.
3. Delay retirement
This lever is the most powerful and the most underrated. Working three extra years does three things at once: (a) three more years of contributions, (b) three more years of compounding, (c) three fewer years your money has to last. The combined effect on retirement-readiness is roughly equivalent to a 30–40% boost in your nest egg. Try it in the calculator — increase retirement age from 65 to 68 and watch the shortfall.
4. Reduce desired retirement spending
The least glamorous lever, but worth being honest about. A €30,000/year retirement requires a much smaller portfolio than a €45,000/year retirement — roughly 33% less. Often people set a desired income that matches their current spending without accounting for the fact that in retirement they no longer commute, don't need work clothes, often have a paid-off house, and frequently have lower medical needs (or fully-subsidised ones) than they assumed.
Why inflation matters so much here
Inflation is the silent destroyer of retirement plans. At 2.5% average inflation, prices roughly double every 29 years. A €35,000 lifestyle today will cost around €72,000/year in 30 years' time — and the calculator's "required nest egg" figure factors that in. If you don't account for inflation, you can be off by a factor of two or more on the size of pot you actually need.
This is also why the "nest egg in today's purchasing power" line matters: a €1.5 million pot in 35 years sounds enormous, but in today's spending power it might only be around €670,000. That's still a lot of money, but it's a different mental anchor than the nominal headline number.
Common retirement-planning mistakes
Treating retirement as a single date
Real retirements often look more like a glide path: full-time work → part-time consulting → fully retired, over 5 to 10 years. Even modest part-time income in your 60s can reduce the size of the portfolio you need by 20–30%, because every euro you don't withdraw is a euro that keeps compounding. Don't assume you're going from 100% income to 0% income overnight.
Ignoring the sequence of returns
Two retirees with identical average returns over 30 years can end up with wildly different outcomes if the bad years cluster at the start of retirement vs. the end. A 30% drop in year 1 of retirement, combined with mandatory withdrawals, can permanently impair the portfolio. This is why most planners suggest holding 1–3 years of expenses in cash or short-term bonds at retirement, so you don't have to sell stocks during a downturn.
Optimising for tax instead of returns
Tax wrappers (3rd-pillar pensions, ISA-equivalents, lijfrente, Riester, etc.) matter — but they shouldn't be the tail wagging the dog. A high-fee tax-advantaged product is often worse than a low-fee taxable product over a 30-year horizon. Always compare net-of-tax-and-fees, not gross.
Frequently asked questions
Should I include state pension / AOW in this calculator?
The calculator doesn't have a separate field for state pension because it varies so much by country and circumstance. The cleanest approach: estimate your state pension as an annual figure, subtract it from your desired annual income, and enter the remainder as "desired annual income." That tells you the size of pot you need from your private investments alone.
Why are the two return rates separate?
Most people shift to a more conservative portfolio mix as they approach and enter retirement — usually a higher bond and cash allocation — to reduce the risk of a bad year ruining the plan. That lower-volatility mix typically returns less. Splitting "before retirement" and "during retirement" rates lets you model that shift honestly without making the calculator pretend you'll stay 100% in stocks at 80.
What if I never want to fully retire?
Then the calculator is still useful as a "what's my F.U. number?" tool — the point at which working becomes optional rather than required. Many people use it to figure out the age at which they could continue their current work by choice, not necessity. Set "years to fund" to your remaining expected lifespan and the required nest egg becomes your full financial independence figure.
How accurate is "years your money lasts"?
It's a deterministic projection assuming constant returns and constant inflation. Real retirements involve sequence-of-returns risk, variable spending, and market volatility. Use this number as a directional indicator, not a guarantee. If the calculator says your money lasts to age 88, treat that as "probably comfortable through your mid-80s, with margin for error" — not as a precise date.
Does the chart show real or nominal balance?
The chart shows nominal balance (the actual euro figure on your account, before adjusting for inflation). The "today's purchasing power" line in the results panel shows the inflation-adjusted equivalent — usually about half the nominal figure over a 30-year horizon. Both numbers are useful: nominal is what your bank app will show, real is what it actually buys.