Retirement Calculator
Project your retirement nest egg and find out if you're on track.
What this calculator does
This retirement calculator projects what your pension and savings grow into by the age you intend to stop working, then converts that pot into the monthly income it can sustain. Enter your current age, retirement age, existing savings, monthly contribution, expected return, and a withdrawal rate, and it returns the projected pot, the income it supports, and a year-by-year table splitting contributions from investment growth.
The contributions-versus-growth split is the part to study. For the first decade or so almost everything in the pot is money you paid in. Later, growth overtakes contributions permanently, which is why starting five years earlier tends to matter more than paying in slightly more each month.
When to use it
The obvious moment is when deciding what to contribute, whether that is at a new job, after a pay rise, or when your employer offers to match above the auto-enrolment minimum. Working backwards from a target monthly income to the contribution that delivers it makes the trade-off with today's take-home pay concrete.
It is also useful for testing a retirement age against the pension access rules. Setting a retirement age of 55 today, when access rises to 57 in 2028, exposes a bridging problem early enough to do something about it. Running two retirement ages side by side shows what each extra working year is worth.
Understanding the inputs
Current savings should include every workplace pension from previous employers, any SIPP, and stocks and shares ISAs you would genuinely use for retirement. Old pensions from jobs held years ago are the single most commonly forgotten input. Monthly contribution must include the employer's share and any tax relief, since all of it compounds identically.
Expected return matters more than anything else here. Six to seven percent nominal is reasonable for a global equity fund before charges; subtract your platform and fund fees, because a 1 percent total charge removes a meaningful slice of a 30-year projection. Withdrawal rate should be nearer 3.5 percent than 4 if you retire in your fifties.
How is this calculated?
FV = PV(1+r)^n + PMT×[(1+r)^n − 1]/r. Nest Egg Needed = Monthly Income / Withdrawal Rate.
A worked example
A 40-year-old with £60,000 already saved, paying in £600 a month at 6 percent, reaches roughly £786,000 by age 67. Of that, £254,400 is contributions and the rest is growth. At a 4 percent withdrawal rate the pot supports around £31,400 a year gross, on top of a full State Pension of roughly £11,970.
Increase the contribution to £900 a month and the pot rises to about £1,028,000. Hold the contribution at £600 but plan on a more cautious 3.5 percent withdrawal rate and the sustainable income falls to around £27,500 a year, which is the cost of assuming a longer, safer drawdown.
Limitations and assumptions
This is a projection under fixed assumptions rather than a forecast. It applies one flat return every year, which no real fund delivers, and the order in which returns arrive matters enormously. A poor few years immediately after you start drawing down does far more damage than the same years in the middle of retirement, even at an identical average.
It also ignores income tax on withdrawals, the 25 percent tax-free element, the State Pension, changing contributions over a career, and fund charges unless you deduct them from the return yourself. Treat the pot figure as the middle of a wide range and rerun it as your circumstances change.
Common Questions
- How large a pension pot do I actually need?
- Divide the annual income you want your own savings to produce by your withdrawal rate. Wanting £30,000 a year at 4 percent implies a £750,000 pot. The State Pension covers part of your income, so subtract it first: the full new State Pension is around £230 a week, roughly £11,970 a year.
- Does this include the State Pension?
- No, and that is deliberate. Work out your target income, subtract your expected State Pension, and size the pot around the remainder. You need 35 qualifying National Insurance years for the full amount and at least 10 to receive anything. Check your record and forecast on the government's State Pension forecast service.
- When can I actually get at the money?
- Personal and workplace pensions are normally accessible from age 55, rising to 57 from April 2028. If you set a retirement age below that in this calculator, the projected pot exists on paper but cannot be drawn from a pension. Bridging those years requires ISAs or other savings outside the pension wrapper.
- How much should I be paying in?
- Auto-enrolment minimums are 8 percent of qualifying earnings, of which the employer must provide at least 3 percent. That is a floor, not a plan. A common target is a percentage equal to half your age when you start, so 15 percent from age 30, rising if you begin later.
- Does the annual allowance cap my contributions?
- Yes. Most people can contribute up to £60,000 a year across all pensions, or 100 percent of UK relevant earnings if lower. High earners can see this tapered down considerably, and unused allowance from the previous three tax years can sometimes be carried forward. Anything above your allowance should go into an ISA instead.
- Are the figures in today's money?
- No, the pot is a future nominal amount. The inflation rate you enter shows what that sum is worth in today's purchasing power. At 2.5 percent inflation a pound loses roughly half its value over 28 years, so a projected pot of £800,000 in 2053 buys what around £400,000 buys today.
- What about the 25 percent tax-free lump sum?
- This projection is pre-tax throughout. In practice you can normally take a quarter of a defined contribution pot free of tax, capped by the lump sum allowance of £268,275, with the remainder taxed as income when drawn. That materially changes your net income, so treat this pot figure as gross.
- What if I am behind?
- Contribute more, work longer, or plan to spend less. Delaying retirement is usually the strongest lever because it adds growth years and removes drawdown years simultaneously. Salary sacrifice is the other underused one: it saves employee National Insurance as well as income tax, so more reaches the pot per pound of take-home given up.
- How often should I rerun this?
- Annually is enough, ideally alongside your pension statement or after a pay rise. The projected pot will move constantly and that is not the signal. What matters is whether your contribution has kept pace with your salary and whether your fund charges and investment mix still suit your time horizon.
Related calculators
- Retirement Withdrawal CalculatorCalculate how long your retirement savings last at different withdrawal rates.
- Retirement Gap CalculatorIdentify the gap between your projected retirement savings and your income goal.
- Retirement Longevity CalculatorCalculate the risk of outliving your retirement savings.