FI Number Calculator
Find the exact portfolio size you need to be financially independent - and how long it will take to get there.
Learn how this calculator works →Your numbers
How much you expect to spend each year in retirement, including housing, bills, food, and leisure. Exclude mortgage if it will be paid off.
The total value of all your invested assets today. Include ISAs, pensions (SIPPs), and general investment accounts. Exclude property, cash savings, and emergency funds.
How much you add to your investments each year, including pension contributions (employee + employer) and ISA deposits.
The nominal (before inflation) return you expect. A global equity tracker has historically returned 7-10% per year.
The Bank of England targets 2%. Higher inflation means your money buys less each year, so you need a larger pot.
Real return: 4.4% · All figures in today's money.
What happens to my data?
Your FI number
£625,000
Based on £25,000/year at a 4% withdrawal rate
Timeline to FI
31
years
Age 61
target retirement age
Portfolio progress
0%£625,000 still to go
Portfolio projection
How your savings rate affects the timeline
Saving more shortens your path to FI - often faster than chasing higher returns.
| Annual savings | Monthly | Years to FI | Retire at |
|---|---|---|---|
| £5,000 | £417 | 44 | Age 74 |
| £7,500 | £625 | 36 | Age 66 |
| £10,000 ← current | £833 | 31 | Age 61 |
| £15,000 | £1,250 | 25 | Age 55 |
| £20,000 | £1,667 | 21 | Age 51 |
Want to understand the maths?
Read: The Ransom Price - Calculating Your Financial Independence Number →The article behind the calculator. How the 4% rule works and why it matters.
Year-by-year breakdown
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Important: Not Financial Advice
This calculator is provided for educational and illustrative purposes only. Freedom Isn't Free is not authorised or regulated by the Financial Conduct Authority (FCA) and does not provide financial advice, investment recommendations, or tax guidance.
The projections shown are hypothetical, assume a constant rate of return, and do not account for inflation, taxes, or fees. Actual investment returns vary and you may get back less than you invest. Past performance is not a reliable indicator of future results.
Before making any financial decisions, please consult with an independent financial adviser regulated by the FCA. For help finding an adviser, visit MoneyHelper or Unbiased.
Where links to financial products appear on this page, some may be affiliate links. See our full disclaimer for details.
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