Coast Fire Calculator

Background.

This coast fire page is built to test whether current invested assets could compound to a retirement target without further contributions. Coast FIRE means the existing portfolio is large enough, under entered assumptions, to reach spending divided by a withdrawal rate at retirement. The implemented convention is “project current invested assets with no further contributions and compare with annual retirement spending / selected withdrawal rate.”

The editable entries are current invested assets, target annual retirement spending, selected retirement withdrawal rate, expected annual real growth rate, years until retirement. Use values from the document or measurement that governs this coast fire question; the defaults are only the worked fixture below. It is a nominal projection with a constant return; taxes, inflation, volatility and future contributions are excluded. If that coast fire condition is not true, choose a calculation that models the missing convention.

U.S. SEC Investor.gov, Stocks; shares, market value and corporate actions documents the convention or governing rule used here. The coast fire output is a transparent scenario under those facts: it does not manufacture an unentered market price, professional determination, carrier quote, legal eligibility finding or locally adopted code value.

What is coast fire calculator?

Coast Fire is the relationship behind this decision: coast FIRE means the existing portfolio is large enough, under entered assumptions, to reach spending divided by a withdrawal rate at retirement. On this page it means project current invested assets with no further contributions and compare with annual retirement spending / selected withdrawal rate. It is a nominal projection with a constant return; taxes, inflation, volatility and future contributions are excluded; that is the line between the reported quantity and a broader retirement analysis.

How to use this calculator.

1. 01Confirm that “project current invested assets with no further contributions and compare with annual retirement spending / selected withdrawal rate” matches the coast fire convention you need.
2. 02Replace the fixture values for current invested assets, target annual retirement spending, selected retirement withdrawal rate, expected annual real growth rate, years until retirement with dated values from the governing record.
3. 03Keep all currencies, measurement units and time periods on the same basis before calculating.
4. 04Read projected balance minus target at retirement together with this boundary: It is a nominal projection with a constant return; taxes, inflation, volatility and future contributions are excluded.

The formula.

The calculation uses project current invested assets with no further contributions and compare with annual retirement spending / selected withdrawal rate. In this coast fire model, the entered terms are current invested assets, target annual retirement spending, selected retirement withdrawal rate, expected annual real growth rate, years until retirement. Coast FIRE means the existing portfolio is large enough, under entered assumptions, to reach spending divided by a withdrawal rate at retirement, which is why the relationship is presented under this name rather than as a universal alternative. It is a nominal projection with a constant return; taxes, inflation, volatility and future contributions are excluded. Calculations keep full decimal precision through the relationship and round only the returned display values.

A worked example.

Frequently asked questions.

References& sources.

1. [1]U.S. SEC Investor.gov, Stocks; shares, market value and corporate actions. Retrieved 2026-08-07. access: open unless marked otherwise.
2. [2]U.S. Social Security Administration. Plan for retirement. Retrieved 2026-08-07. independence: primary; access: open.
3. [3]U.S. Internal Revenue Service. Publication 590-A, Contributions to Individual Retirement Arrangements. Retrieved 2026-08-07. independence: primary; access: open.