Coast FIRE Guides
Explanations of Coast FIRE formulas, assumptions, comparisons, and life-scenario calculations.
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📘Coast FIRE Fundamentals
What Is Coast FIRE?
A complete introduction to Coast FIRE — what it means, how it works, and why it matters for your financial independence journey.
Read Guide →How Coast FIRE Works
Understand the three phases of Coast FIRE: Build, Coast, and Retire. Learn how compound growth does the heavy lifting.
Read Guide →🔢Calculations & Formulas
Coast FIRE Calculator Troubleshooting
Understand unexpected Coast FIRE results: unchanged targets, inflation, contributions, return assumptions, input errors and differences between calculators.
Read Guide →Coast FIRE Formula Explained
Learn the Coast FIRE formula in simple terms. See what each number means, follow an easy example, and understand why age, return, inflation, and retirement spending change the result.
Read Guide →How to Calculate Your Coast FIRE Number
Step-by-step guide to calculating your personal Coast FIRE number with real examples and adjustable assumptions.
Read Guide →⚖️Assumptions & Rates
What Return Rate Should a Coast FIRE Calculator Use?
There is no single return rate that is universally correct for a Coast FIRE calculator. Learn how return assumptions affect the calculation.
Read Guide →Real Return vs Nominal Return in Coast FIRE
Nominal return is investment growth before adjusting for inflation. Real return measures growth after accounting for inflation.
Read Guide →How Withdrawal-Rate Assumptions Change Your Coast FIRE Number
A withdrawal-rate assumption changes a Coast FIRE calculation because it determines the modeled retirement portfolio target.
Read Guide →🗺️Life Scenarios
🎯Strategy & Planning
Is Coast FIRE Worth It?
There is no universal yes-or-no answer to whether Coast FIRE is “worth it.” A Coast FIRE calculator can measure what happens when current invested assets are projected toward a future retirement target under selected assumptions.
Read Guide →Common Coast FIRE Mistakes
Most Coast FIRE errors come from one of two places: the calculation uses inconsistent inputs, or the result is interpreted as meaning more than the calculation actually shows.
Read Guide →What Happens After Reaching Coast FIRE?
What happens after reaching Coast FIRE? See how continued contributions, market changes, spending, work, benefits, and changing assumptions affect the modeled Coast FIRE scenario.
Read Guide →When Have You Reached Coast FIRE?
You have reached the modeled Coast FIRE target when your current invested assets are at or above the Coast FIRE number calculated for your current age, selected retirement age, retirement spending, and calculation assumptions.
Read Guide →🔄Comparisons
Coast FIRE vs Barista FIRE: What's the Difference?
Compare Coast FIRE vs Barista FIRE, including portfolio growth, part-time income, current spending, withdrawals, health coverage, and why the two models produce different numbers.
Read Guide →Coast FIRE vs Lean FIRE: What's the Difference?
Compare Coast FIRE vs Lean FIRE and see why one describes a future-growth milestone while the other describes a lower-spending portfolio target. Includes consistent examples.
Read Guide →Coast FIRE vs Fat FIRE: What's the Difference?
Compare Coast FIRE vs Fat FIRE and see how timing, higher retirement spending, portfolio targets, taxes, healthcare, and assumptions change the mathematical model.
Read Guide →Coast FIRE vs FIRE: What's the Difference?
Coast FIRE vs FIRE explained using one consistent example. Compare the modeled targets, contributions, retirement timing, current spending, and what each calculation actually measures.
Read Guide →Compare the Concepts With Your Inputs
The calculator applies the documented formula to the values and assumptions you enter.
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