Field guide · Career flexibility
Begin with the monthly cash gap.
For an illustrative break or reduction in hours, compare dependable monthly net income with realistic spending.
Use cash that is already available
Choose the accessible cash included in your scenario and any amount you want to leave untouched. Subtract that amount once. Keep pensions, unvested awards and assumed future share-sale proceeds outside the calculation.
Use payslips, statements and bills to create consistent household figures. Include occasional costs in an appropriate monthly estimate rather than overlooking them.
The arithmetic
Usable cash ÷ (monthly spending − dependable monthly net income) gives a simple months-of-cover illustration when spending exceeds income.
For example, £24,000 of usable cash, £3,000 monthly spending and £1,000 monthly income give a £2,000 monthly shortfall and 12 months of illustrative cover.
If income equals or exceeds spending, this arithmetic shows no monthly shortfall. It does not prove that a long-term plan is secure.
Explore cash runwayWhat the illustration leaves out
The tool assumes constant income and spending. It excludes inflation, returns, unexpected costs and future changes. The amount left untouched is your input, not a recommended emergency reserve.
Use the example to frame questions about flexibility and uncertainty, then review the broader plan with an appropriate professional.