What is the Coast FIRE Calculator?
The Coast FIRE Calculator helps you work out how much you need invested today so that, with no further pension or ISA contributions, your money can grow to fund retirement later. It’s designed for UK investors who want to know when they can stop aggressively saving for retirement and simply “coast” on a lower-stress income that just covers day-to-day living costs.
How the Calculator Works?
This calculator models your retirement goal amount, target retirement age and expected investment growth to find the pot size you need today for Coast FIRE. It projects how that pot could grow over time with compound returns and no further contributions, then compares it with your chosen retirement income needs, withdrawal rate and any State Pension you choose to include. You can also add your current pensions, ISAs and GIAs to see how close you already are to your Coast FIRE number.
Step One: Set Your Retirement Target
Choose your target retirement age and the annual income you’d like in retirement. Add your expected safe withdrawal rate and decide whether to include the State Pension in your plan.
Step Two: Enter Your Current Investments
Add your existing pension, ISA and GIA balances, plus any other long-term investments. Set your assumed long-term growth rate so the calculator can project how your pot might grow between now and retirement.
Step Three: Discover Your Number
The calculator shows the pot size you’d need today to reach your retirement goal without any further contributions. It then compares this to your current investments so you can see how close you are to Coast FIRE and how tweaks to growth, retirement age or income affect your path.
Disclaimer:
This calculator provides illustrative projections only and should not be taken as financial advice. Investment returns and personal circumstances can change over time, so consider speaking with a qualified financial adviser before making major financial decisions.
What does retirement mean to you?
Traditional retirement is broken. Understand how our calculator enables you to live a better life now vs later.
Retire from corporate work?
Use the tool to utilise how you can step away from the corporate world and live life on your own terms.
Work less, live more
See how part-time or project-based work can bridge your income gap while giving you more time for life.
Freedom through planning
Understand how your savings, spending and investments can work together to buy back your time.
Test-drive retirement early
Model scenarios that let you experience elements of retirement before fully stepping away.
What is the Coast FIRE Calculator
The Coast FIRE Calculator estimates how much you’d need invested today for your portfolio to grow to your desired retirement income level by your target retirement age, assuming no further contributions. It also shows how your current pensions, ISAs and GIAs compare to that Coast FIRE number.
What is Coast FIRE?
Coast FIRE is a stage on the financial independence journey where you’ve already built enough invested wealth that, if left to grow, it should reach your retirement target without any further contributions. From that point on, you only need to earn enough to cover your current living costs, rather than continuing to save heavily for retirement.
How does it work?
The tool takes your current age, target retirement age, desired retirement income, withdrawal rate, and growth assumptions. It then works backwards to find the starting pot required today so that, with compound growth, it can reach the value needed to support your planned retirement income. Your current investments are then measured against that target.
What information do I need to use the tool?
You’ll need:
- Your current age
- Your target retirement age
- Your desired annual retirement income
- Your current pension, ISA and GIA balances
- Your assumed long-term investment growth rate
- Your chosen safe withdrawal rate
- Whether you want to include the State Pension, and from what age
The more realistic your inputs, the more useful the results.
Does this calculator include the State Pension?
Yes. You can choose whether to include it and at what age. Including the State Pension will often reduce the pot size required for Fat FIRE or Lean FIRE later in life.
Is Coast FIRE the same as full FIRE?
No. Full FIRE means you can stop working entirely, and your investments cover all your living costs right now. Coast FIRE means you’ve built enough for retirement later, but in the meantime, you still need to work (often in a more relaxed or enjoyable role) to cover current living expenses.
How accurate are the results?
The results are estimates based on your assumptions. Actual investment returns, inflation and life events will vary. The calculator is best used as a planning tool to understand rough targets and trade-offs, not as a guarantee.
What growth rate should I use?
That’s a personal choice and not a prediction. Many people use a conservative real (after-inflation) return or a nominal return with inflation in mind. You can try a range of growth rates to see how optimistic or cautious assumptions affect your Coast FIRE number.
Is my information saved or stored?
No. All calculations run in your browser. We do not store, transfer or retain any personal data.
Can this replace a financial adviser?
No. This tool provides a reliable benchmark and planning framework, but it cannot account for the full complexity of your financial situation. For personalised advice, speak to a qualified financial adviser