Transparent method
The formula
Worked example
Example inputs
How to interpret the result
Fat FIRE targets a materially higher spending level than standard FIRE, which means it's disproportionately exposed to lifestyle inflation creeping in before the target's reached. A spending plan set today at a higher standard of living tends to keep rising with income along the way, which continuously pushes the target further out even as the portfolio grows.
Before you rely on it
What to check
Re-run the target periodically against actual current spending, not the original planning-stage spending figure, since a higher-spending plan is more sensitive to drift over a long accumulation period.
The common error
Where people go wrong with fat FIRE calculator
Locking in a fat FIRE spending target early and never revisiting it. Lifestyle inflation tends to be larger in dollar terms at a higher spending level, and an unrevised target can end up meaningfully understating what retirement will actually cost by the time it arrives.
Sensitivity evidence
How withdrawal rate changes the FIRE portfolio target
| Withdrawal rate | FIRE portfolio target | Estimated years to target |
|---|---|---|
| 2.0% | $6,000,000 | 26.0 years |
| 3.0% | $4,000,000 | 20.0 years |
| 4.0%worked example | $3,000,000 | 16.0 years |
| 5.0% | $2,400,000 | 13.0 years |
| 6.0% | $2,000,000 | 11.0 years |
Every input, tested
Which input moves the FIRE portfolio target most
| Input | Tested from | To | FIRE portfolio target at each end | Swing |
|---|---|---|---|---|
| Withdrawal rate | 3.0% | 5.0% | $4,000,000 to $2,400,000 | $1,600,000 (53%) |
| Annual spending | $108,000 | $132,000 | $2,700,000 to $3,300,000 | $600,000 (20%) |
| Current invested assets | $540,000 | $660,000 | $3,000,000 to $3,000,000 | none |
| Annual investments | $54,000 | $66,000 | $3,000,000 to $3,000,000 | none |
| Expected annual return | 5.0% | 7.0% | $3,000,000 to $3,000,000 | none |
Two variables at once
FIRE portfolio target by withdrawal rate and annual spending
| Withdrawal rate \ Annual spending | $96,000 | $120,000 | $144,000 |
|---|---|---|---|
| 2.0% | $4,800,000 | $6,000,000 | $7,200,000 |
| 3.0% | $3,200,000 | $4,000,000 | $4,800,000 |
| 4.0% | $2,400,000 | $3,000,000 | $3,600,000 |
| 5.0% | $1,920,000 | $2,400,000 | $2,880,000 |
| 6.0% | $1,600,000 | $2,000,000 | $2,400,000 |
Step by step
The worked example, input by input
| Input | Value used |
|---|---|
| Annual spending | $120,000 |
| Withdrawal rate | 4.0% |
| Current invested assets | $600,000 |
| Annual investments | $60,000 |
| Expected annual return | 6.0% |
| FIRE portfolio target | $3,000,000 |
| Estimated years to target | 16.0 years |
Complete evidence
Full projection schedule
Show all 10 rows
| Period | Opening balance | Contribution | Growth | Ending balance |
|---|---|---|---|---|
| Year 1 | $600,000 | $60,000 | $36,000 | $696,000 |
| Year 2 | $696,000 | $60,000 | $41,760 | $797,760 |
| Year 3 | $797,760 | $60,000 | $47,866 | $905,626 |
| Year 4 | $905,626 | $60,000 | $54,338 | $1,019,963 |
| Year 5 | $1,019,963 | $60,000 | $61,198 | $1,141,161 |
| Year 6 | $1,141,161 | $60,000 | $68,470 | $1,269,631 |
| Year 7 | $1,269,631 | $60,000 | $76,178 | $1,405,808 |
| Year 8 | $1,405,808 | $60,000 | $84,349 | $1,550,157 |
| Year 9 | $1,550,157 | $60,000 | $93,009 | $1,703,166 |
| Year 10 | $1,703,166 | $60,000 | $102,190 | $1,865,356 |
Where the inputs come from
Fat FIRE targets a comfortable or generous lifestyle, often $100,000 or more in yearly spending. Build the figure from a realistic budget that includes housing, travel, healthcare, hobbies, gifts and larger home costs. Current assets and annual investments will be larger than in a lean plan. Choose a return you can defend, since a big portfolio depends heavily on the assumption. Use after-fee returns.
Using the FIRE portfolio target in a real decision
Consider whether the extra years of work are worth the extra spending, since each additional $10,000 of yearly spending adds $250,000 to the target.
When the result stops applying
Higher spending brings more tax: large withdrawals from traditional accounts can push income into higher brackets and trigger Medicare surcharges. Concentration risk can be larger with a big portfolio, such as company stock. Lifestyle inflation can make the budget expand as the portfolio grows. Estate and legacy goals may need a lower withdrawal rate.
What to compare it with
Compare with the standard and lean FIRE pages, and use the retirement withdrawal order and income tax calculators to see how withdrawals are taxed. The Roth conversion and IRMAA pages help manage large balances. The Monte Carlo calculator stress-tests the plan.
People also ask
Frequently asked questions
What is Fat FIRE?
Financial independence at a high spending level, typically well over $100,000 a year, requiring a much larger portfolio than standard or lean FIRE.
How is Fat FIRE different in practice?
The larger portfolio brings tax planning, asset allocation and estate questions that smaller plans avoid, and it usually needs a long or high-earning career.
Should a large portfolio use a lower withdrawal rate?
Often yes, especially for early retirees or those who want to leave an inheritance, since a lower rate raises the chance the money lasts.