How much do you need for Lean, Barista and Fat FIRE in the UK?
Which FIRE lifestyle fits your future?
This calculator lets you compare Lean FIRE (minimalist), Barista FIRE (part-time work supported) and Fat FIRE (comfort-focused) to see how much wealth each requires. Adjust spending, income and growth assumptions to discover when each version of FIRE becomes achievable for you.
How the Calculator Works?
This calculator runs three retirement scenarios in parallel: Lean FIRE, Barista FIRE, and Fat FIRE. Each scenario represents a different lifestyle cost, from essential spending through to a fully comfortable retirement. The tool applies your investment growth, withdrawal rate and contribution assumptions to calculate the pot size required for each lifestyle, how long each scenario is sustainable and much more.
Step One: Enter Your Financial Details
Add your current assets, pension and ISA balances, yearly contributions, expected growth rate and chosen safe withdrawal rate. These inputs form the base for all three FIRE calculations.
Step Two: Set Your Lean, Barista & Fat FIRE Spending Levels
Define the annual spending you associate with Lean FIRE (essential lifestyle), Barista FIRE (part-time supported lifestyle) and Fat FIRE (comfortable lifestyle). You can also add optional income for the Barista scenario if relevant.
Step Three: Compare Your Path to Each FIRE Lifestyle
The calculator shows the required pot size for each FIRE tier and estimates when you could reach that milestone based on your current trajectory. Adjust your assumptions to see how contributions, spending, returns and withdrawal rates change your FIRE timelines.
Disclaimer:
This calculator provides illustrative projections only and should not be taken as financial advice. FIRE outcomes depend heavily on individual circumstances, risk tolerance and market conditions. For personalised guidance, consider speaking with a qualified financial adviser.
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 Lean / Barista / Fat FIRE Comparison Tool?
The Lean / Barista / Fat FIRE Comparison Tool helps you understand how much wealth you need for three different FIRE lifestyles in the UK. By modelling your spending levels, contributions, investment growth, and withdrawal rate, it calculates the pot required for Lean FIRE, Barista FIRE, and Fat FIRE. It shows how achievable each path is based on your current trajectory.
What are Lean, Barista and Fat FIRE?
Lean FIRE: A minimalist lifestyle with low annual spending and a smaller required pot.
Barista FIRE: Semi-retirement supported by part-time work or small income streams.
Fat FIRE: A comfortable lifestyle with higher spending and a larger required pot.
What information do I need to use the tool?
You’ll need your current portfolio values (pensions, ISAs, GIAs), monthly contributions, expected investment growth, withdrawal rate and your chosen Lean/Barista/Fat FIRE spending levels.
Does the Barista FIRE option include partial income?
Yes. You can add part-time work, consulting income or hobby income to see how even small amounts of extra earnings can significantly reduce the pot needed for Barista FIRE.
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.
How do I choose the right spending level for each FIRE category?
It depends on your lifestyle preferences. Many users base Lean FIRE on essential expenses only, Barista FIRE on their current lifestyle with reduced work hours, and Fat FIRE on a more comfortable version of their current spending. You can adjust the numbers anytime and instantly see the impact.
Can I adjust assumptions like inflation or fees?
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