How the calculation works
The goal follows from your spending and the withdrawal rate. Then the calculator adds your savings month by month until the goal is reached.
Goal = yearly spending ÷ withdrawal rate
Balance after the month = balance × (1 + monthly return) + monthly saving
The monthly return is (1 + yearly return)1/12 − 1. The calculation stops when the balance reaches the goal, or after 100 years.Worked example
Yearly spending 24,000, withdrawal rate 4%, no savings yet, 2,000 saved a month, 0% return.
- Goal: 24,000 ÷ 0.04 = 600,000.
- Saving 2,000 a month without any return takes 600,000 ÷ 2,000 = 300 months.
- That is 25 years. A positive return makes it shorter.
What this calculator does not include
- Taxes, fees, pensions and state benefits.
- Returns that change from year to year, and the risk of a bad start.
- Changes in your spending or saving over time.
Amounts are rounded for display only; the calculation itself is not rounded. Results are estimates for information, not financial advice. Last updated: 13 November 2026.
Frequently asked questions
What does financial independence mean?
It means your savings are large enough that withdrawals from them can pay for your living costs, so you no longer have to work for money. The calculator shows the savings you need and how long it takes to build them.
What is the withdrawal rate?
The share of your savings you take out each year. A common rule of thumb is 4%, which means you need 25 times your yearly spending. A lower rate is safer and needs more savings. It is a guide, not a guarantee.
Why should I enter the return after inflation?
The calculator works in today’s money. If you enter a return after inflation, the goal and your savings stay comparable over the years. For example, 7% growth with 2.5% inflation is about 4.4% after inflation.
How accurate is the time it shows?
It is a simple model with a steady return. Real returns go up and down, and the years just before and after you stop working matter most. Treat the result as a rough direction and test lower returns as well.
What is not included?
Taxes, fees, pensions, state benefits, one-off costs and a change in your spending. Add them to your own plan or ask an adviser.