Calculator Inputs
Designed for large screens (3 columns), smaller screens (2), and mobile (1).
Example Data Table
Sample values show how inputs can translate into a funding target. Numbers are illustrative and will vary with assumptions.
| Scenario | Monthly Expenses | Support Years | Debts | Existing Savings | Existing Cover | Estimated Target |
|---|---|---|---|---|---|---|
| Balanced | $2,500 | 20 | $60,000 | $20,000 | $50,000 | $530,000 |
| Higher inflation | $2,500 | 20 | $60,000 | $20,000 | $50,000 | $610,000 |
| Lower return | $2,500 | 20 | $60,000 | $20,000 | $50,000 | $665,000 |
Tip: Try changing just one assumption (inflation or return) to see sensitivity.
Formula Used
This calculator estimates a present-value fund that could support your family’s net living needs while accounting for inflation.
1) Net monthly need
Net Monthly Need = max(Monthly Expenses − Partner Income − Other Income, 0)
2) Income replacement fund (growing annuity present value)
PV = P × [1 − ((1+g)/(1+r))^n] / (r − g)
Where P is net annual need, n is support years,
g is inflation, and r is expected return.
3) Total security fund
Total Need = PV + Debts + Education + Final Expenses + Emergency Fund + Buffer
Emergency Fund = Net Monthly Need × Emergency Months
Buffer = Base Total Need × Buffer %
When return and inflation are nearly equal, a stable approximation is used to avoid numerical issues.
How to Use This Calculator
- Enter realistic monthly living expenses for your household.
- Add steady incomes that could continue (partner income, rentals, pensions).
- Set support years based on your dependents’ timeline.
- Include one-time provisions like debts, education, and final expenses.
- Choose inflation and expected return assumptions conservatively.
- Set a buffer to cover uncertainty and unexpected costs.
- Press Calculate and review the gap, breakdown, and optional monthly saving.
- Download CSV for records, or export a PDF for sharing.