What this calculator does

Use this emergency fund calculator to estimate a cash buffer from your essential monthly expenses and chosen months of cover. Add current emergency savings and a monthly saving amount to see your target, remaining gap, current coverage and estimated time to reach it.

Formula used

Emergency fund target equals essential monthly expenses multiplied by target months. For example, six months of GBP 1,800 in essential monthly costs gives a target of GBP 10,800. Savings gap equals the target minus current emergency savings. Estimated time to target equals the remaining gap divided by monthly saving.

How to read the result

Three to six months of essential costs can be a useful starting range, but the right target depends on income stability, dependants, debt commitments and how quickly unexpected costs could be covered. Use the result as a planning target rather than a fixed rule.

Assumptions

  • Uses essential monthly costs, not full lifestyle spending.
  • Treats the target months you enter as a planning choice rather than a universal recommendation.
  • Does not include interest earned on the emergency fund.
  • Assumes the same monthly saving is made every month.

Sources and checks

This calculator uses a standard public formula. Where rules or thresholds can change, source links are listed on the relevant page.

Frequently asked questions

How do I calculate my emergency fund?

Multiply your essential monthly expenses by the number of months you want to cover. Then subtract the emergency savings you already have to find the remaining savings gap.

How many months should an emergency fund cover?

Three to six months of essential costs is a useful starting range for many planning scenarios, but income stability, dependants, debt and access to other support can justify a smaller or larger target.

Should I use gross income or expenses?

Expenses usually make a better target because the fund is there to cover bills, food, transport and other essentials during a disruption.