What is the Financial Runway Calculator?
The Financial Runway Calculator helps you estimate how long your accessible money could last while you explore a life or career change.
It is designed for people thinking about a sabbatical, part-time work, retraining, starting a business, or simply creating more breathing room. By entering your savings, investments, yearly spend, and return assumptions, you can see how much time your money might buy.
How the Calculator Works?
The calculator focuses on accessible money, such as cash savings, a Stocks and Shares ISA, and a general investment account. It compares those balances against your typical yearly spend, then adjusts for any other income you expect to receive.
It applies your chosen return assumptions to ISA and GIA investments, with a separate interest assumption for cash. The main result shows your estimated runway based on your inputs, while the comparison view shows how different return assumptions could change the outcome.
The model uses a simple withdrawal order of cash first, then GIA, then ISA. This keeps the output easy to follow and helps you understand how your balance may change over time.
Step 1: Enter Your Accessible Money
Add your cash savings, Stocks and Shares ISA, and GIA balances. These should be pots you could realistically use to support a life or career change.
Step 2: Add Your Spending and Income
Enter your typical yearly spend and any other yearly income, such as freelance work, BTL income, or a small side business.
Step 3: Review Your Runway
See how long your money could last based on your assumptions, compare different return scenarios, and review how your balance may change over time.
Disclaimer: This calculator provides illustrative projections only and should not be taken as financial advice. It is a planning tool based on simplified assumptions, not a guarantee of how long your money will last.
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 your financial runway could make room for
A financial runway is about knowing how much time your money could give you to make a change. These examples show how different people might use the calculator to test their options.
Emma, planning a sabbatical
Emma has built up savings and wants to understand whether she could take time away from work without putting herself under pressure.
- Tests cash and ISA balances together
- Uses a realistic yearly spend
- Checks how long her runway could last
James, starting a business
James wants to leave full-time employment and give a new business idea a proper chance, while allowing for some income to build over time.
- Adds expected side income
- Models different return assumptions
- Sees how much breathing room he has
Sophie, retraining for a new career
Sophie is considering a course and a lower income period while she changes career. She wants to know what level of spending feels manageable.
- Compares current and reduced spending
- Checks how savings may be used over time
- Downloads the numbers for planning
What is the Financial Runway Calculator?
The Financial Runway Calculator is a planning tool that estimates how long your accessible savings and investments could support you while you make a life or career change. It helps you test your runway using your own balances, yearly spend, other income, and return assumptions.
What does the Financial Runway Calculator do?
It estimates how long your accessible money could support your spending if you took time out, reduced work, retrained, or explored a new direction.
What counts as accessible money?
Accessible money usually means cash savings, ISAs, and general investment accounts. It generally does not include pensions, property equity, or money you cannot easily use.
Should I include my pension?
Usually no. This calculator is focused on money available today or in the near term. Pension money may be locked until later life, so it is not the main focus of this tool.
What spending figure should I use?
Use a realistic yearly spend. This could be your current annual spending or a lower figure if you expect to reduce costs during a sabbatical or career change.
Can I include other income?
Yes. You can include yearly income from part-time work, freelance income, BTL rent, dividends, or any other income you reasonably expect.
How are investment returns modelled?
The calculator applies a flat return assumption to ISA and GIA investments. Cash savings use a separate interest assumption. These are simplified modelling inputs.
What does the quick comparison show?
The quick comparison shows how your runway could change under different return assumptions, such as 3%, 5%, 7%, or 9%.
What withdrawal order does the calculator use?
The calculator assumes money is used from cash first, then GIA, then ISA. This is a simple modelling choice to make the projection easier to understand.
Does this include tax?
No. It does not model tax in detail. GIA taxation, ISA rules, income tax, and personal circumstances are simplified or excluded.
Is this a retirement calculator?
Not really. It can support retirement-style thinking, but it is mainly designed for mid-career flexibility, sabbaticals, retraining, part-time work, or starting something new.
How accurate are the results?
The results are illustrative. They depend heavily on your spending, return assumptions, and actual investment performance.
Is my information stored?
No. The calculator is designed to run in your browser. Any CSV or email export flow is separate from the calculation itself.
Trust and education
Certified Money First Aider®
These calculators are built by a Certified Money First Aider to help you think more clearly about money and time. Money First Aid® is about practical, non-judgemental support for financial wellbeing. The calculators can certainly help you make informed decisions, but they are not regulated financial advice.
