In plain text
Target = (S) ÷ (w) Savings today = (Target) ÷ ((1+r)^(t))
What is Coast FIRE?
FIRE stands for financial independence, retire early. Coast FIRE is a stage within that idea. You have saved enough that compound growth alone should carry you to your retirement goal, so you could stop adding new savings and still retire on time. You may still need to earn enough to cover your current living costs.
How do I use it?
Enter the retirement savings you have now, your current age, and the age you plan to retire. Then enter the yearly spending you expect in retirement, the withdrawal rate you plan to live on, and the return you assume the savings will earn. The results show the retirement target, the savings needed today, the value your savings reach by retirement, and whether you have reached the coast point.
How does the calculation work?
The retirement target is the yearly spending divided by the withdrawal rate. This is the savings amount that would support that spending at the rate you chose. The savings needed today is the target divided by the growth factor for the years until retirement, where the growth factor adds the return to the starting amount and raises that sum to the number of years.
The value at retirement is your current savings multiplied by the same growth factor. If that value is at least the target, your savings are on track without new contributions.
Why does the withdrawal rate matter?
The withdrawal rate sets how large a nest egg you need. A lower rate means a bigger target, because you draw less each year. A higher rate means a smaller target, but it leaves less margin if markets fall or you live longer than planned. Many people compare a few rates before choosing one.
What can the result not tell me?
The calculator uses a steady return for every year and does not model market swings, taxes on withdrawals, or inflation. It does not include Social Security, pensions, or other income in retirement, which would reduce how much you need to save.
The result is an estimate based on the assumptions you enter. Change the return and withdrawal rates to see how sensitive the result is before you rely on it.
Why is a coast point not the same as stopping work?
Reaching the coast point means you could stop adding to retirement savings and still have enough by your target age. It does not mean you can stop working, because you still need income for current costs such as housing, food, and health care. Many people use the point to change to lower-paid or more flexible work.
How does this relate to other retirement tools?
The compound interest and savings goal calculators show how a balance grows with regular deposits, while this tool asks how much must be saved today with no more deposits. Use them together to see whether a plan works with or without future contributions.
