What Is Chubby FIRE?
Chubby FIRE is an informal label for a retirement budget between leaner and more expensive FIRE plans. The label has no fixed dollar threshold or regulatory definition. Your household size, location, taxes, healthcare, and other income determine the portfolio-funded spending that matters for this calculation.
Use this free calculator to compare accumulation scenarios with a spending-based target. It models changing contributions and a constant return for 50 years. Reaching the target is an arithmetic milestone, not evidence that retirement withdrawals will remain sustainable.
How to Use This Chubby FIRE Calculator
- 1
Enter Your Current Net Worth
Start with your total investable assets — stocks, bonds, savings accounts, retirement accounts, and other investments. Exclude your primary residence and personal property unless you plan to sell them.
- 2
Set Your Investment Return Rate
Enter an effective annual return as a scenario assumption. The calculator uses monthly growth of (1 + annual return)^(1/12) − 1. If you choose an inflation-adjusted return, keep spending and contribution assumptions in the same purchasing-power basis; the tool has no separate inflation input.
- 3
Configure Your Contributions
Enter the amount for each monthly, quarterly, or annual contribution. Growth changes that amount after each chosen one-, two-, or five-year interval. Contributions enter after monthly growth; quarterly and annual schedules start at the end of the first modeled month, then repeat every three or twelve months.
- 4
Define Your Chubby FIRE Target
Enter annual spending funded by this portfolio and a hypothetical withdrawal rate. Target = annual spending ÷ withdrawal rate as a decimal. Other income, tax treatment, and changing costs need separate consideration; the formula does not establish a safe retirement budget.
- 5
Review Your Projection
Click Get Result to see the first modeled target crossing and rolling twelve-month balances. Contributions continue through the full 50-year display even after the target is reached. No retirement spending is deducted from that chart.
FIRE Levels Compared
The labels below are informal categories. The dollar bands are illustrative budgets chosen for this comparison, not standard definitions or evidence of affordability. Every displayed portfolio range equals the example annual budget divided by 4%; choosing a different rate changes every result.
Minimal spending, frugal lifestyle
Comfortable middle-class lifestyle
Above-average lifestyle, comfortable spending
Higher illustrative spending budget
Largest illustrative spending budget
Who Is Chubby FIRE For?
The useful question is whether your assumptions match your household. These planning situations require different budgets and constraints:
Mid-to-Senior Professionals
Test what remains available to invest after taxes, debt payments, and current expenses. A particular salary or job title does not establish that an early-retirement target is feasible.
Dual-Income Households
Enter the combined amount actually available to this portfolio. Include a scenario with reduced contributions if either income stops; the default model does not simulate unemployment.
Lifestyle-Conscious Planners
Separate essential expenses from discretionary travel, dining, and hobbies. Compare more than one annual spending target instead of assuming one dollar band buys the same lifestyle everywhere.
Risk-Aware Retirees
Budget for healthcare and unexpected costs explicitly. A larger target lowers the initial spending-to-assets ratio, but this calculator does not quantify market-loss probabilities or retirement longevity.
Assumptions to Compare Before Using the Projection
Test Sustainable Contributions
Compare contribution amounts you could maintain alongside current obligations. Change one input at a time to see its effect; the tool does not choose a savings rate for your household.
Check Contribution Growth
Treat contribution growth as an assumption to test. A 10% annual increase compounds rapidly: $1,000 per month becomes about $2,594 in the eleventh modeled year. Future income may not support that path.
Account for Fees in the Return Assumption
The return input is a simplified constant net growth assumption. Investment expenses are not deducted separately, so do not enter a gross return and assume the model has accounted for fund or advisory fees.
Review Account Constraints Separately
Account eligibility, contribution limits, withdrawal access, and tax treatment differ. This calculator does not distinguish account types or calculate taxes, and cannot determine which account to fund first.
Test a Higher Spending Budget
Compare a higher spending target with the base case. At a hypothetical 4% rate, each additional $10,000 of annual portfolio-funded spending adds $250,000 to the target.
Compare Contribution Timing
Compare starting balances and contribution timing without treating a constant-rate chart as a market forecast. Earlier contributions have more modeled growth periods when returns are positive; losses and interrupted saving can change the outcome.
Chubby FIRE Example Scenario
A Zero-Return Arithmetic Check
For a reproducible example, enter age 30, $250,000 invested, $1,000 monthly contributions, 0% contribution growth, 0% return, $20,000 annual spending, and a 4% withdrawal rate. The target is $500,000. It is first crossed after 250 contributions, or 20 years and 10 months, at $500,000; the rounded-up years field shows 21. These deliberately simple assumptions isolate the contribution arithmetic.
Build a Household Budget
A spending number is not a promise about housing, travel, or healthcare. Build an itemized budget, distinguish gross withdrawals from spendable cash, and check whether other income starts later. The calculator holds the target constant unless you change the input.
Chubby FIRE Withdrawal Strategies
Initial Withdrawal with Inflation Adjustments
In William Bengen's original historical withdrawal research, the starting withdrawal was a percentage of the initial portfolio, followed by inflation-adjusted dollar withdrawals. This is different from taking 4% of the current balance every year. Results depend on the studied history, portfolio, and horizon; this accumulation tool does not reproduce that study.
Variable Percentage Withdrawal
Taking a set percentage of the current balance changes the cash available each year. A lower balance produces lower spending. This differs from an inflation-adjusted dollar withdrawal and may fail to meet essential expenses even if a positive balance remains.
Bucket Strategy
A bucket approach separates holdings by intended spending horizon, but still requires allocation and replenishment rules. This tool has one aggregate balance and does not model separate cash, bond, or stock buckets.