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Five realistic UK profiles - median earner, late starter, FI saver, mortgage payoff, ISA-led. One click and you'll see year-by-year projections come to life.
Uncrystallised
Crystallised
Cash ISA
Stocks ISA
Current Acc
Wealth over time
Pots and spending target
+£100/m to pension
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Retire 1 year later
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Pension growth +1%
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Monte Carlo
Will your money last?
Rather than one fixed-return guess, this runs your plan through 2,000 randomised market paths and reports how often it survives. Your one-off stress-crash is switched off here so it isn't double-counted with the randomness.
Shaded bands show the range of total wealth across the paths; the line is the median. Returns are modelled lognormally (realistic ups and downs, no impossible losses below -100%). Randomised each run, so figures wobble a point or two.
In the worst outcomes, when does the money actually run out?
How each small decision moves your success rate, tested on the same market paths.
The income (in today's £) that hits each confidence level. 95% is the practical "very safe" line; true 100% usually just means underspending.
Read it as a trade-off: spend less for near-certainty, more for a riskier plan. Income is in today's money; success is the share of 2,000-path runs with no shortfall to your end age.
Projection
Year-by-year ledger
Useful providers
More on FAQCommon UK platforms for holding a SIPP or ISA. Compare against your own situation before opening an account.
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